doc: document behavior change in image/color in release notes
doc: document behavior change in image/color in release notes

Change-Id: I7ad90ab78abb8a39d56c837610d5c311a96b7039
Reviewed-on: https://go-review.googlesource.com/12162
Reviewed-by: Nigel Tao <58ae08b3356928ff9c67562b4719487d54fe8348@golang.org>

nakedgc/go,kakuhiroshi/go,fjballest/golang,akutz/go,cookerzhu/go,cnbin/go,binarycrusader/go,gohin/go,miolini/go,beealone/go,Badredapple/go,ifagnosticism/go,jonahglover/go,beealone/go,pgmreddy/go,b54898533/go,jdeng/go,joshsammut/go,jonathanmarvens/go,skatsuta/go,theif519/go,danycoro/go,dkolbly/go,mgyenik/go,RBEGamer/go,xiuzhifu/go,jefby/go,greyhwndz/go,miolini/go,gdey/go,constantine001/go,magastzheng/go-1,WIZARD-CXY/go,andrewchambers/go,suncycheng/go,mikekap/go,yangzhongj/go,4ad/go,vsekhar/elastic-go,magastzheng/go-1,jacobhaven/go,greyhwndz/go,alash3al/go,cainiaocome/go,nawawi/go,yeyuguo/go,stormltf/go,goodlang/good,magastzheng/go-1,jonathanmarvens/go,Jordanzuo/go,xinhuang327/go,skotti/go,AALEKH/go,uileyar/go,JioCloud/go,ErikDubbelboer/go,monetate/go,odeke-em/go,theif519/go,dterei/go,vsdutka/go,momchil-velikov/go,Stan-Lin-/go,yuhengye/go,youprofit/go,ganboing/go-esx,joshsammut/go,kim-racktop/go,arschles/golang-go,jonathanmarvens/go,springning/go,zcwfeng/go,arschles/go-1,dterei/go,likesea/go,zcwfeng/go,Jordanzuo/go,constantine001/go,donnel6809/go,willjunspecial/go,Young55555/go,jameskumar/go,jameskumar/go,linux-on-ibm-z/go,momchil-velikov/go,xujianhai/go,PoohSunny/go,Pulgafree/go,b54898533/go,xiuzhifu/go,leeric92/go,vishsingh/go,vsdutka/go,jdeng/go,willjunspecial/go,cnbin/go,ObjectiveJoe/go,ImJasonH/go,PoohSunny/go,NunoEdgarGub1/go,mbrukman/go,arschles/golang-go,parkdy/go,dkolbly/go,Jordanzuo/go,cloudrain21/go,Stan-Lin-/go,mdp/go,fjballest/golang,jacobsa/go,zhangg/go,donnel6809/go,jonathanmarvens/go,golang/go,jacobsa/go,derekmarcotte/go,jameskumar/go,dpatel06/go,gohin/go,famorted/go,cloudrain21/go,xiaobodu/go,cyberroadie/go,zcwfeng/go,GeorgiCodes/go,goodlang/good,suncycheng/go,springning/go,momchil-velikov/go,theass/go,zhangg/go,vishsingh/go,cloudrain21/go,Endika/go,Cofyc/go,jonasi/go,kevinc0825/go,Cofyc/go,vsekhar/elastic-go,kevinc0825/go,yuhengye/go,Pulgafree/go,danycoro/go,likesea/go,gdey/go,nakedgc/go,deft-code/go,jacobsa/go,greyhwndz/go,monetate/go,skotti/go,Jordanzuo/go,jmptrader/go,malvira/go,Jordanzuo/go,9618211/go,xinhuang327/go,mbrukman/go,wangfakang/go-1,malvira/go,4ad/go,yasarkunduz/go,jonasi/go,shazow/go,Samurais/go,yasarkunduz/go,snowsnail/go,mgyenik/go,albertjin/golang-go,CAFxX/go,gdey/go,dterei/go,albertjin/golang-go,jacobxk/go,XuYunnan/go,honsiorovskyi/go,jacobxk/go,dpatel06/go,RBEGamer/go,yangzhongj/go,RBEGamer/go,Samurais/go,alash3al/go,monetate/go,yangzhongj/go,jonasi/go,zouchao2010/go,mwhudson/go,Jordanzuo/go,leeric92/go,cainiaocome/go,PoohSunny/go,Stan-Lin-/go,jmptrader/go,danielsoro/go,donnel6809/go,theif519/go,GeorgiCodes/go,CiscoCloud/go,likesea/go,joshsammut/go,mdp/go,g522342435/go,kevinc0825/go,jonahglover/go,arschles/golang-go,kim-racktop/go,vishsingh/go,mdp/go,yasarkunduz/go,yuhengye/go,willjunspecial/go,gdey/go,youprofit/go,constantine001/go,xujianhai/go,roth1002/go,constantine001/go,parkdy/go,myPublicGit/go,b54898533/go,dgnorton/go,Charlesdong/go-1,jonahglover/go,zhangg/go,sosop/go,fjballest/golang,b54898533/go,chinanjjohn2012/go,cnbin/go,vsekhar/elastic-go,mdp/go,ObjectiveJoe/go,joshsammut/go,linux-on-ibm-z/go,devpadawan/go,ichu501/go,danielsoro/go,yeyuguo/go,sosop/go,lihuanghai/go,arschles/go-1,suncycheng/go,cloudflare/go,rentongzhang/go,RBEGamer/go,WIZARD-CXY/go,mbrukman/go,josharian/go,vsekhar/elastic-go,cainiaocome/go,mwhudson/go,springning/go,golang/go,cookerzhu/go,zouchao2010/go,NichoZhang/go,GeorgiCodes/go,JioCloud/go,9618211/go,JioCloud/go,ifagnosticism/go,royels/go,mgyenik/go,jdhenke/go,alex-zhang/go,PoohSunny/go,andrewchambers/go,codestation/go,CarterTsai/go,cnbin/go,skotti/go,g522342435/go,jmptrader/go,ImJasonH/go,miolini/go,CodyGuo/go,alash3al/go,mbrukman/go,mwhudson/go,jefby/go,ganboing/go-esx,jasonxiong/go,shazow/go,JioCloud/go,royels/go,mwhudson/go,skotti/go,springning/go,xujianhai/go,rachtsingh/gogojuice,ericsnowcurrently/go,roth1002/go,rachtsingh/gogojuice,AALEKH/go,ganboing/go-esx,binarycrusader/go,xiaobodu/go,mdp/go,ErikDubbelboer/go,GeorgiCodes/go,Young55555/go,codestation/go,baiyunping333/go,youprofit/go,albertjin/golang-go,sosop/go,famorted/go,vanloswang/go,jmptrader/go,jameskumar/go,gohin/go,springning/go,sndnvaps/go,Cofyc/go,cyberroadie/go,nakedgc/go,theif519/go,rentongzhang/go,momchil-velikov/go,devpadawan/go,WIZARD-CXY/go,youprofit/go,dkolbly/go,JioCloud/go,sinuos/go,yuhengye/go,shazow/go,shines77/go,joshsammut/go,shishkander/go,Endika/go,ichu501/go,pgmreddy/go,yasarkunduz/go,shines77/go,deft-code/go,honsiorovskyi/go,skatsuta/go,beealone/go,CiscoCloud/go,suncycheng/go,XuYunnan/go,jdeng/go,xiaobodu/go,Young55555/go,vanloswang/go,snowsnail/go,jonathanmarvens/go,CAFxX/go,jacobhaven/go,NunoEdgarGub1/go,suncycheng/go,shines77/go,yuhengye/go,lihuanghai/go,ErikDubbelboer/go,RBEGamer/go,leeric92/go,chinanjjohn2012/go,PoohSunny/go,devpadawan/go,Pulgafree/go,kim-racktop/go,stormltf/go,mikekap/go,uileyar/go,g522342435/go,ichu501/go,josharian/go,ifagnosticism/go,dterei/go,jonahglover/go,shines77/go,yangzhongj/go,slavau/go,Young55555/go,gohin/go,suncycheng/go,arschles/go-1,NichoZhang/go,momchil-velikov/go,NunoEdgarGub1/go,vishsingh/go,albertjin/golang-go,myPublicGit/go,agaurav/go,Samurais/go,baiyunping333/go,ObjectiveJoe/go,kim-racktop/go,chinanjjohn2012/go,kevinc0825/go,Jordanzuo/go,ifagnosticism/go,royels/go,beealone/go,dafyddcrosby/go,andrewchambers/go,mdp/go,dkolbly/go,beealone/go,willjunspecial/go,kim-racktop/go,cloudflare/go,mwhudson/go,undergrowthlinear/go,ErikDubbelboer/go,Endika/go,stormltf/go,binarycrusader/go,jdhenke/go,vsdutka/go,Charlesdong/go-1,rentongzhang/go,jameskumar/go,zcwfeng/go,royels/go,golang/go,jonasi/go,arschles/go-1,rachtsingh/gogojuice,xinhuang327/go,chinanjjohn2012/go,cloudflare/go,beealone/go,yasarkunduz/go,dterei/go,jacobhaven/go,shishkander/go,polyverse-security/go,roth1002/go,weisd/go,codestation/go,fjballest/golang,WIZARD-CXY/go,rentongzhang/go,donnel6809/go,pgmreddy/go,ifagnosticism/go,GeorgiCodes/go,skatsuta/go,polyverse-security/go,mdp/go,9618211/go,Badredapple/go,codestation/go,yuhengye/go,jefby/go,shazow/go,agaurav/go,jasonxiong/go,derekmarcotte/go,binarycrusader/go,vsdutka/go,CarterTsai/go,CarterTsai/go,jefby/go,honsiorovskyi/go,theass/go,leeric92/go,yangzhongj/go,nawawi/go,dpatel06/go,rachtsingh/gogojuice,jacobhaven/go,chinanjjohn2012/go,odeke-em/go,slavau/go,binarycrusader/go,dafyddcrosby/go,likesea/go,undergrowthlinear/go,vsdutka/go,myPublicGit/go,golang/go,cloudrain21/go,ObjectiveJoe/go,ericsnowcurrently/go,4ad/go,jonahglover/go,vsdutka/go,NichoZhang/go,donnel6809/go,xiaobodu/go,9618211/go,pgmreddy/go,stormltf/go,mwhudson/go,famorted/go,CarterTsai/go,theif519/go,fjballest/golang,NichoZhang/go,AALEKH/go,yasarkunduz/go,nakedgc/go,uileyar/go,Stan-Lin-/go,shishkander/go,danielsoro/go,Charlesdong/go-1,snowsnail/go,jacobxk/go,akutz/go,jdhenke/go,9618211/go,NunoEdgarGub1/go,jasonxiong/go,vanloswang/go,kakuhiroshi/go,undergrowthlinear/go,alash3al/go,derekmarcotte/go,miolini/go,goodlang/good,linux-on-ibm-z/go,zouchao2010/go,kakuhiroshi/go,akutz/go,Badredapple/go,pgmreddy/go,NichoZhang/go,cloudrain21/go,yeyuguo/go,vishsingh/go,ericsnowcurrently/go,yeyuguo/go,theif519/go,yangzhongj/go,sinuos/go,jdhenke/go,andrewchambers/go,vsdutka/go,alex-zhang/go,ericsnowcurrently/go,jacobxk/go,greyhwndz/go,ErikDubbelboer/go,vishsingh/go,cnbin/go,cookerzhu/go,malvira/go,yeyuguo/go,donnel6809/go,miolini/go,RBEGamer/go,dpatel06/go,dterei/go,pgmreddy/go,stormltf/go,jdhenke/go,PoohSunny/go,gdey/go,nawawi/go,CarterTsai/go,danycoro/go,linux-on-ibm-z/go,akutz/go,danielsoro/go,ganboing/go-esx,famorted/go,mikekap/go,jasonxiong/go,skotti/go,donnel6809/go,CAFxX/go,xiuzhifu/go,myPublicGit/go,ichu501/go,PoohSunny/go,agaurav/go,rentongzhang/go,pgmreddy/go,royels/go,PoohSunny/go,uileyar/go,momchil-velikov/go,zcwfeng/go,Charlesdong/go-1,springning/go,constantine001/go,xinhuang327/go,CiscoCloud/go,Stan-Lin-/go,cainiaocome/go,theass/go,b54898533/go,nawawi/go,kevinc0825/go,uileyar/go,snowsnail/go,skotti/go,mikekap/go,willjunspecial/go,cloudflare/go,vishsingh/go,miolini/go,fjballest/golang,jonasi/go,ObjectiveJoe/go,leeric92/go,ifagnosticism/go,xiuzhifu/go,yeyuguo/go,wangfakang/go-1,dafyddcrosby/go,arschles/golang-go,malvira/go,shazow/go,AALEKH/go,snowsnail/go,4ad/go,XuYunnan/go,ganboing/go-esx,goodlang/good,beealone/go,goodlang/good,greyhwndz/go,qskycolor/go,xiuzhifu/go,dpatel06/go,myPublicGit/go,xujianhai/go,deft-code/go,andrewchambers/go,wangfakang/go-1,CodyGuo/go,yasarkunduz/go,Cofyc/go,cloudrain21/go,agaurav/go,g522342435/go,kakuhiroshi/go,alex-zhang/go,cookerzhu/go,cloudrain21/go,greyhwndz/go,GeorgiCodes/go,jacobsa/go,shishkander/go,zouchao2010/go,dgnorton/go,alex-zhang/go,gohin/go,sinuos/go,qskycolor/go,mbrukman/go,shazow/go,4ad/go,linux-on-ibm-z/go,kevinc0825/go,qskycolor/go,willjunspecial/go,stormltf/go,mikekap/go,sinuos/go,wangfakang/go-1,constantine001/go,baiyunping333/go,albertjin/golang-go,constantine001/go,WIZARD-CXY/go,zouchao2010/go,9618211/go,vsekhar/elastic-go,shishkander/go,nakedgc/go,shines77/go,Charlesdong/go-1,arschles/golang-go,9618211/go,willjunspecial/go,XuYunnan/go,golang/go,odeke-em/go,ImJasonH/go,undergrowthlinear/go,mikekap/go,xinhuang327/go,danycoro/go,ganboing/go-esx,theass/go,dkolbly/go,magastzheng/go-1,xiuzhifu/go,youprofit/go,binarycrusader/go,xujianhai/go,jdeng/go,gohin/go,derekmarcotte/go,polyverse-security/go,ichu501/go,jonasi/go,WIZARD-CXY/go,xiaobodu/go,qskycolor/go,samanalysis/go,zcwfeng/go,nawawi/go,cyberroadie/go,CiscoCloud/go,theif519/go,jacobhaven/go,mikekap/go,nakedgc/go,fjballest/golang,mbrukman/go,xiaobodu/go,arschles/go-1,sndnvaps/go,josharian/go,sndnvaps/go,g522342435/go,shazow/go,gdey/go,andrewchambers/go,jacobxk/go,jonahglover/go,greyhwndz/go,jdeng/go,leeric92/go,codestation/go,CiscoCloud/go,weisd/go,shishkander/go,theass/go,xujianhai/go,sndnvaps/go,goodlang/good,AALEKH/go,CarterTsai/go,samanalysis/go,Cofyc/go,CarterTsai/go,undergrowthlinear/go,vanloswang/go,Stan-Lin-/go,ericsnowcurrently/go,jameskumar/go,agaurav/go,uileyar/go,sinuos/go,NunoEdgarGub1/go,sosop/go,monetate/go,josharian/go,miolini/go,joshsammut/go,arschles/golang-go,cyberroadie/go,4ad/go,famorted/go,mgyenik/go,g522342435/go,youprofit/go,cookerzhu/go,mwhudson/go,undergrowthlinear/go,b54898533/go,Endika/go,ErikDubbelboer/go,xiuzhifu/go,undergrowthlinear/go,cookerzhu/go,cnbin/go,zhangg/go,akutz/go,magastzheng/go-1,jasonxiong/go,RBEGamer/go,danycoro/go,shines77/go,cyberroadie/go,Pulgafree/go,zcwfeng/go,polyverse-security/go,royels/go,shazow/go,NichoZhang/go,ichu501/go,Charlesdong/go-1,skatsuta/go,arschles/golang-go,kim-racktop/go,jasonxiong/go,Endika/go,agaurav/go,malvira/go,odeke-em/go,ErikDubbelboer/go,magastzheng/go-1,jacobsa/go,ImJasonH/go,albertjin/golang-go,roth1002/go,royels/go,NunoEdgarGub1/go,jameskumar/go,jdhenke/go,JioCloud/go,XuYunnan/go,CarterTsai/go,g522342435/go,gohin/go,nawawi/go,Samurais/go,kakuhiroshi/go,danycoro/go,andrewchambers/go,dafyddcrosby/go,odeke-em/go,Endika/go,xujianhai/go,roth1002/go,alex-zhang/go,odeke-em/go,likesea/go,dterei/go,parkdy/go,NunoEdgarGub1/go,honsiorovskyi/go,lihuanghai/go,golang/go,leeric92/go,arschles/go-1,jacobsa/go,josharian/go,fjballest/golang,gdey/go,theass/go,mgyenik/go,skatsuta/go,ericsnowcurrently/go,Pulgafree/go,jacobsa/go,myPublicGit/go,mgyenik/go,sinuos/go,slavau/go,baiyunping333/go,dkolbly/go,dpatel06/go,sndnvaps/go,cyberroadie/go,Samurais/go,jdhenke/go,joshsammut/go,xinhuang327/go,yuhengye/go,sinuos/go,kim-racktop/go,yeyuguo/go,ganboing/go-esx,4ad/go,jasonxiong/go,constantine001/go,Endika/go,dgnorton/go,Charlesdong/go-1,golang/go,arschles/golang-go,jonasi/go,likesea/go,dgnorton/go,myPublicGit/go,vanloswang/go,ObjectiveJoe/go,cloudrain21/go,qskycolor/go,CiscoCloud/go,weisd/go,jacobhaven/go,ganboing/go-esx,CodyGuo/go,undergrowthlinear/go,g522342435/go,devpadawan/go,codestation/go,Young55555/go,mbrukman/go,willjunspecial/go,arschles/go-1,wangfakang/go-1,golang/go,gdey/go,devpadawan/go,kim-racktop/go,sosop/go,jefby/go,zouchao2010/go,derekmarcotte/go,mbrukman/go,Pulgafree/go,roth1002/go,CodyGuo/go,xiuzhifu/go,ImJasonH/go,youprofit/go,lihuanghai/go,deft-code/go,samanalysis/go,ImJasonH/go,vsekhar/elastic-go,linux-on-ibm-z/go,cloudflare/go,jdeng/go,xiaobodu/go,CAFxX/go,theass/go,ericsnowcurrently/go,skotti/go,mikekap/go,jacobhaven/go,akutz/go,b54898533/go,vishsingh/go,zouchao2010/go,GeorgiCodes/go,vanloswang/go,likesea/go,ObjectiveJoe/go,dafyddcrosby/go,polyverse-security/go,snowsnail/go,parkdy/go,xinhuang327/go,baiyunping333/go,samanalysis/go,sinuos/go,mgyenik/go,derekmarcotte/go,greyhwndz/go,danielsoro/go,shishkander/go,ifagnosticism/go,weisd/go,XuYunnan/go,roth1002/go,stormltf/go,springning/go,ichu501/go,danycoro/go,Young55555/go,jonasi/go,weisd/go,shines77/go,CodyGuo/go,famorted/go,kakuhiroshi/go,samanalysis/go,danielsoro/go,CAFxX/go,Stan-Lin-/go,jasonxiong/go,yasarkunduz/go,slavau/go,magastzheng/go-1,qskycolor/go,akutz/go,odeke-em/go,cookerzhu/go,zcwfeng/go,WIZARD-CXY/go,cainiaocome/go,polyverse-security/go,mgyenik/go,nakedgc/go,deft-code/go,Stan-Lin-/go,sosop/go,dafyddcrosby/go,agaurav/go,CAFxX/go,jacobxk/go,Charlesdong/go-1,lihuanghai/go,malvira/go,uileyar/go,GeorgiCodes/go,Badredapple/go,Samurais/go,slavau/go,baiyunping333/go,danielsoro/go,momchil-velikov/go,AALEKH/go,slavau/go,gohin/go,Young55555/go,binarycrusader/go,chinanjjohn2012/go,AALEKH/go,JioCloud/go,samanalysis/go,nakedgc/go,CAFxX/go,shines77/go,Jordanzuo/go,yangzhongj/go,rachtsingh/gogojuice,deft-code/go,CodyGuo/go,baiyunping333/go,linux-on-ibm-z/go,weisd/go,qskycolor/go,4ad/go,christopher-henderson/Go,agaurav/go,polyverse-security/go,uileyar/go,andrewchambers/go,rachtsingh/gogojuice,derekmarcotte/go,springning/go,jdeng/go,kevinc0825/go,cainiaocome/go,wangfakang/go-1,arschles/go-1,dgnorton/go,ObjectiveJoe/go,derekmarcotte/go,yangzhongj/go,xinhuang327/go,CodyGuo/go,skatsuta/go,slavau/go,Cofyc/go,cainiaocome/go,linux-on-ibm-z/go,ErikDubbelboer/go,goodlang/good,ImJasonH/go,monetate/go,NichoZhang/go,dkolbly/go,monetate/go,jacobsa/go,rachtsingh/gogojuice,momchil-velikov/go,yuhengye/go,shishkander/go,danycoro/go,yeyuguo/go,albertjin/golang-go,dgnorton/go,cloudflare/go,kevinc0825/go,Badredapple/go,dafyddcrosby/go,CAFxX/go,Badredapple/go,cookerzhu/go,binarycrusader/go,theass/go,kakuhiroshi/go,suncycheng/go,nawawi/go,alash3al/go,jonahglover/go,alash3al/go,lihuanghai/go,zhangg/go,monetate/go,dgnorton/go,rachtsingh/gogojuice,jonathanmarvens/go,ichu501/go,albertjin/golang-go,NichoZhang/go,zhangg/go,nawawi/go,xujianhai/go,qskycolor/go,chinanjjohn2012/go,honsiorovskyi/go,royels/go,samanalysis/go,slavau/go,samanalysis/go,wangfakang/go-1,zouchao2010/go,jonathanmarvens/go,XuYunnan/go,dkolbly/go,sosop/go,jdeng/go,AALEKH/go,Pulgafree/go,CiscoCloud/go,dpatel06/go,zhangg/go,devpadawan/go,jameskumar/go,JioCloud/go,chinanjjohn2012/go,josharian/go,pgmreddy/go,akutz/go,devpadawan/go,polyverse-security/go,Endika/go,kakuhiroshi/go,jmptrader/go,alash3al/go,Pulgafree/go,alex-zhang/go,Badredapple/go,theif519/go,deft-code/go,wangfakang/go-1,malvira/go,dterei/go,jmptrader/go,Badredapple/go,parkdy/go,jonathanmarvens/go,skatsuta/go,donnel6809/go,rentongzhang/go,joshsammut/go,magastzheng/go-1,cnbin/go,ImJasonH/go,famorted/go,odeke-em/go,vsdutka/go,danielsoro/go,alex-zhang/go,CiscoCloud/go,skotti/go,Young55555/go,suncycheng/go,sndnvaps/go,jacobhaven/go,leeric92/go,9618211/go,jefby/go,b54898533/go,alex-zhang/go,malvira/go,honsiorovskyi/go,zhangg/go,baiyunping333/go,cloudflare/go,lihuanghai/go,RBEGamer/go,dpatel06/go,roth1002/go,likesea/go,sndnvaps/go,vanloswang/go,NunoEdgarGub1/go,codestation/go,jacobxk/go,jmptrader/go,xiaobodu/go,deft-code/go,vanloswang/go,Samurais/go,cnbin/go,vsekhar/elastic-go,honsiorovskyi/go,cloudflare/go,josharian/go,dgnorton/go,weisd/go,ericsnowcurrently/go,jonahglover/go,monetate/go,parkdy/go,jefby/go,mwhudson/go,sndnvaps/go,parkdy/go,WIZARD-CXY/go,Cofyc/go,snowsnail/go,parkdy/go,alash3al/go,lihuanghai/go,stormltf/go,cainiaocome/go,jefby/go,XuYunnan/go,Cofyc/go,famorted/go,josharian/go,miolini/go,weisd/go,devpadawan/go,beealone/go,goodlang/good,sosop/go,youprofit/go,CodyGuo/go,snowsnail/go,codestation/go,rentongzhang/go,Samurais/go,dafyddcrosby/go,jdhenke/go,mdp/go,rentongzhang/go,cyberroadie/go,myPublicGit/go,ifagnosticism/go,jmptrader/go,jacobxk/go,honsiorovskyi/go,skatsuta/go,cyberroadie/go,vsekhar/elastic-go