New flag for repo upload: --current_branch (--cbr)
New flag for repo upload: --current_branch (--cbr)

A convenient equivalent to `repo upload --br=<current git branch>`.

Note that the head branch will be selected for each project
uploaded by repo, so different branches may be uploaded for
different projects.

Change-Id: I10ad8ceaa63f055105c2d847c6e329fa4226dbaf

eligoenergy/git-repo,kdavis-mozilla/repo-repo,sapiippo/git-repo,azzurris/git-repo,xyyangkun/git-repo,crashkita/git-repo,bhargavkumar040/android-source-browsing.git-repo,Jokebin/git-repo,zbunix/git-repo,llg84/google_repo,zodsoft/git-repo,xxxrac/git-repo,idwanglu2010/git-repo,COrtegaflowcorp/git-repo,sb2008/git-repo,lipro-yocto/git-repo,ericmckean/git-repo,amersons/git-repo,nbp/git-repo,chenzilin/git-repo,nucked/git-repo,qioixiy/git-repo,CedricCabessa/repo,daimajia/git-repo,jingyu/git-repo,lchiocca/repo,darrengarvey/git-repo,crashkita/git-repo,alanbian/git-repo,kangear/git-repo,qupai/git-repo,mixedpuppy/git-repo,hejq0310/git-repo,SunRain/repo,aep/repo,GatorQue/git-repo-flow,hackbutty/git-repo,FuangCao/git-repo,linux-knight/repo,flingone/git-repo,Omnifarious/git-repo,mozilla/git-repo,djibi2/git-repo,posix4e/git-repo,dsiganos/git-repo,aosp-mirror/tools_repo,GatorQue/git-repo-flow,eric011/git-repo,LA-Toth/git-repo,liaog/git-repo,xin3liang/git-repo,ThangBK2009/android-source-browsing.git-repo,zemug/repo,codetutil/git-repo,hanw/git-repo,nuclearmistake/repo,lchiocca/repo,CyanogenMod/tools_repo,enochcheng/git-repo,FuangCao/repo,luohongzhen/git-repo,fantasyfly/git-repo,AurelienBallier/git-repo,ilansmith/repo,FlymeOS/repo,linuxdeepin/git-repo,HenningSchroeder/git-repo,duralog/repo,CedricCabessa/repo,nuclearmistake/repo,IbpTeam/repo,windyan/git-repo,lightsofapollo/git-repo,couchbasedeps/git-repo,lshain/repo,alessandro-aglietti/git-repo,martinjina/git-repo,cubieboard/git-repo,mer-tools/git-repo,jingyu/git-repo,testbetta/git-repo-pub,yanjiegit/andriod-repo,lewixliu/git-repo,DavidPu/git-repo,Pivosgroup/google-git-repo,TheQtCompany/git-repo,Pivosgroup/google-git-repo,hisilicon/git-repo,opencontrail-ci-admin/git-repo,qingpingguo/git-repo,aep/repo,SaleJumper/android-source-browsing.git-repo,cubieboard/git-repo,xecle/git-repo,loungin/git-repo,dinpot/git-repo,mer-tools/git-repo,iAlios/git-repo,jcfrank/myrepo,xin3liang/git-repo,gbraad/git-repo,opencontrail-ci-admin/git-repo,eligoenergy/git-repo,baidurom/repo,derron/git-repo,chenyun90323/git-repo,bhargavkumar040/android-source-browsing.git-repo,11NJ/git-repo,lanniaoershi/git-repo,Copypeng/git-repo,vmx/git-repo,ChronoMonochrome/repo,TheQtCompany/git-repo,ilansmith/repo,ediTLJ/git-repo,hanw/git-repo,4455jkjh/repo,masscre/git-repo,zbunix/git-repo,ediTLJ/git-repo,artprogramming/git-repo,qingpingguo/git-repo,folpindo/git-repo,Jokebin/git-repo,chusiang/git-repo,urras/git-repo,iAlios/git-repo,codetutil/git-repo,xyyangkun/git-repo,dsiganos/git-repo,kdavis-mozilla/repo-repo,hackbutty/git-repo,GerritCodeReview/git-repo,bestes/repo,dsiganos/git-repo,hyper123/git-repo,ronan22/repo,11NJ/git-repo,masscre/git-repo,amersons/git-repo,xecle/git-repo,azzurris/git-repo,hanchentech/git-repo,venus-solar/git-repo,jmollan/git-repo,ceejatec/git-repo,jangle789/git-repo,lewixliu/git-repo,AurelienBallier/git-repo,Omnifarious/git-repo,qioixiy/git-repo,venus-solar/git-repo,chzhong/git-repo,biaolv/git-repo,fantasyfly/git-repo,ronan22/repo,Copypeng/git-repo,gbraad/git-repo,lanniaoershi/git-repo,finik/git-repo,lshain/repo,zemug/repo,jpzhu/git-repo,yanjiegit/andriod-repo,hacker-camp/google_repo,chusiang/git-repo,frogbywyplay/git-repo,llg84/google_repo,petemoore/git-repo,jcfrank/myrepo,cubieboard/git-repo,demonyangyue/git-repo,Fr4ncky/git-repo,mozilla/git-repo,slfyusufu/repo,todototry/git-repo,luohongzhen/git-repo,josn-jys/git-repo,baidurom/repo,windyan/git-repo,vmx/git-repo,chenzilin/git-repo,4455jkjh/repo,bestes/repo,demonyangyue/git-repo,linux-knight/repo,eric011/git-repo,zbunix/git-repo,dinpot/git-repo,IbpTeam/repo,simbasailor/git-repo,DavidPu/git-repo,Pankaj-Sakariya/android-source-browsing.git-repo,weixiaodong/git-repo,testbetta/repo-pub,idwanglu2010/git-repo,zodsoft/git-repo,mixedpuppy/git-repo,petemoore/git-repo,jmollan/git-repo,chzhong/git-repo,derron/git-repo,lipro-yocto/git-repo,HenningSchroeder/git-repo,hanchentech/git-repo,loungin/git-repo,rochy2014/repo,qupai/git-repo,CedricCabessa/repo,folpindo/git-repo,finik/git-repo,nucked/git-repo,CyanogenMod/tools_repo,dodocat/git-repo,Fr4ncky/git-repo,sb2008/git-repo,nbp/git-repo,hyper123/git-repo,ericmckean/git-repo,aep/repo,ThangBK2009/android-source-browsing.git-repo,slfyusufu/repo,COrtegaflowcorp/git-repo,FuangCao/repo,simbasailor/git-repo,testbetta/git-repo-pub,duralog/repo,frogbywyplay/git-repo,jangle789/git-repo,josn-jys/git-repo,aosp-mirror/tools_repo,chenyun90323/git-repo,lightsofapollo/git-repo,xxxrac/git-repo,Pankaj-Sakariya/android-source-browsing.git-repo,linuxdeepin/git-repo,martinjina/git-repo,artprogramming/git-repo,enochcheng/git-repo,finik/git-repo,FuangCao/git-repo,opensourcechipspark/repo,todototry/git-repo,GerritCodeReview/git-repo,linux-knight/repo,hisilicon/git-repo,xianyo/git-repo,Omnifarious/git-repo,yanjiegit/andriod-repo,ChronoMonochrome/repo,alanbian/git-repo,gabbayo/git-repo,rochy2014/repo,SunRain/repo,testbetta/repo-pub,wavecomp/git-repo,gabbayo/git-repo,RuanJG/git-repo,RuanJG/git-repo,wzhy90/git-repo,ceejatec/git-repo,alessandro-aglietti/git-repo,djibi2/git-repo,jpzhu/git-repo,xianyo/git-repo,opensourcechipspark/repo,kangear/git-repo,daimajia/git-repo,posix4e/git-repo,hejq0310/git-repo,wavecomp/git-repo,biaolv/git-repo,SaleJumper/android-source-browsing.git-repo,LA-Toth/git-repo,darrengarvey/git-repo,FlymeOS/repo,hacker-camp/google_repo,weixiaodong/git-repo,urras/git-repo,dodocat/git-repo,couchbasedeps/git-repo,wzhy90/git-repo,flingone/git-repo,sapiippo/git-repo,liaog/git-repo