Clarify role of `dockerhost` variable
Clarify role of `dockerhost` variable

Signed-off-by: Alex Coventry <0603d39ff36b2201d45e12891635521788a1d442@empirical.com>

ibuildthecloud/docker,akira-baruah/docker,shhsu/docker,djs55/docker,gnailuy/docker,rremer/moby,yosifkit/docker,twaugh/docker,yongtang/docker,prertik/docker,prertik/docker,kojiromike/docker,yosifkit/docker,allencloud/docker,noironetworks/docker,cyphar/docker,Morsicus/docker,dmcgowan/docker,x1022as/docker,noironetworks/docker,ndeloof/docker,michael-holzheu/docker,kencochrane/docker,erikh/docker,KarthikNayak/docker,q384566678/docker,dgageot/docker,cloudflare/docker,Ramzec/docker,dsau/docker,fcrisciani/docker,resin-io/docker,hqhq/moby,mikedougherty/docker,moul/docker,icaoweiwei/docker,cpuguy83/docker,moul/docker,tonistiigi/docker,srust/docker,djs55/docker,estesp/docker,mahak/docker,endophage/docker,POLJM242/docker,gjaskiewicz/moby,allencloud/docker,yasiramin10p/moby,yasiramin10p/moby,danyalKhaliq10p/moby,haveatry/docker,portworx/docker,imkin/moby,trebonian/docker,ndeloof/docker,ibuildthecloud/docker,mikebrow/docker,dsau/docker,nawawi/docker,duglin/docker,docker/docker,thaJeztah/docker,abhinavdahiya/docker,ibuildthecloud/docker,maxamillion/docker,ndeloof/docker,sterchelen/docker,paralin/docker,trebonian/docker,projectatomic/docker,HuKeping/docker,alfred-landrum/docker,ripcurld0/moby,tophj-ibm/docker,kolyshkin/docker,tklauser/docker,yummypeng/docker,mstanleyjones/docker,gschaetz/moby,sarnautov/moby,13W/docker,coolljt0725/docker,sterchelen/docker,sfsmithcha/docker,sdurrheimer/docker,noironetworks/docker,pramodhkp/moby,dccurtis/docker,estesp/docker,rancher/docker,abhinavdahiya/docker,johnstep/moby-moby,moby/moby,mikebrow/docker,madhanrm/docker,amatsus/docker,bearstech/moby,moypray/docker,SvenDowideit/docker,afein/docker,zhuguihua/docker,mtesselH/docker,13W/docker,nawawi/docker,shishir-a412ed/docker,dperny/docker,rhatdan/docker,mahak/docker,Syntaxide/docker,yp-engineering/docker,sterchelen/docker,lixiaobing1/docker,13W/docker,AkihiroSuda/docker,madhanrm/docker,charleszheng44/moby,miminar/docker,xiaods/docker,lixiaobing1/docker,scotttlin/docker,resin-io/docker,msabansal/docker,thtanaka/docker,HuKeping/docker,laijs/docker,stevvooe/docker,jameszhan/docker,shishir-a412ed/docker,kolyshkin/moby,coreos/docker,bearstech/moby,miminar/docker,xiekeyang/docker,paralin/docker,flavio/docker,gnailuy/docker,mtanlee/docker,wenchma/docker,dccurtis/docker,Morsicus/docker,allencloud/docker,trebonian/docker,mkumatag/docker,jameszhan/docker,jthelin/docker,KarthikNayak/docker,whuwxl/docker,duglin/docker,thaJeztah/docker,xuxinkun/docker,michelvocks/docker,brahmaroutu/docker,jimjag/docker,pradipd/moby,eskaaren/docker,naveed-jamil-tenpearls/moby,KingEmet/docker,ajaymdesai/docker,splunk/docker,yummypeng/docker,pradipd/moby,gjaskiewicz/moby,rhatdan/docker,amatsus/docker,fcrisciani/docker,imkin/moby,dperny/docker,mike1729/docker,HideoYamauchi/docker,justincormack/docker,jvanz/docker,konstruktoid/docker-upstream,13W/docker,diogomonica/docker,justincormack/docker,imkin/moby,mixja/docker,cpuguy83/docker,docker/docker,sdurrheimer/docker,mohmost12/docker,mahak/docker,vdemeester/docker,dsheets/moby,dmcgowan/docker,rremer/moby,diogomonica/docker,xiekeyang/docker,kunalkushwaha/docker,tophj-ibm/docker,jameszhan/docker,jlhawn/docker,SvenDowideit/docker,laijs/moby,mohmost12/docker,mikedougherty/docker,projectatomic/docker,coolljt0725/docker,cpuguy83/docker,tagomoris/docker,yp-engineering/docker,Ramzec/docker,duglin/docker,michelvocks/docker,projectatomic/docker,akira-baruah/docker,hypriot/docker,srust/docker,gschaetz/moby,mtesselH/docker,jvanz/docker,erikstmartin/docker,KingEmet/docker,hypriot/docker,jlhawn/docker,kolyshkin/moby,Ramzec/docker,dsau/docker,YuPengZTE/docker,erikstmartin/docker,scotttlin/docker,JMesser81/docker,jimjag/docker,yosifkit/docker,vdemeester/docker,jimjag/docker,srust/docker,justyntemme/docker,ColinHebert/docker,ffoysal/docker,paralin/docker,tmp6154/docker,mtrmac/docker,stevvooe/docker,crosbymichael/docker,rhatdan/storage,yongtang/docker,ripcurld0/moby,yummypeng/docker,catinthesky/docker,eskaaren/docker,nalind/docker,coreos/docker,dgageot/docker,flavio/docker,containers/storage,containers/storage,naveed-jamil-tenpearls/moby,unclejack/docker,mike1729/docker,icaoweiwei/docker,laijs/moby,tonistiigi/docker,mtesselH/docker,Syntaxide/docker,endophage/docker,jhorwit2/docker,xiaods/docker,JMesser81/docker,sarnautov/moby,dims/docker,sdurrheimer/docker,madhanrm/docker,moypray/docker,alfred-landrum/docker,mkumatag/docker,sfsmithcha/docker,whuwxl/docker,erikh/docker,harche/docker,tagomoris/docker,ffoysal/docker,shishir-a412ed/docker,tmp6154/docker,darrenstahlmsft/docker,rhatdan/storage,HideoYamauchi/docker,charleszheng44/moby,noxiouz/docker,brahmaroutu/docker,tophj-ibm/moby,mikebrow/docker,msabansal/docker,rhatdan/docker,liaoqingwei/docker,darrenstahlmsft/moby,asbjornenge/docker,tianon/docker,pramodhkp/moby,tianon/docker,konstruktoid/docker-1,nalind/docker,jthelin/docker,resin-io/docker,HuKeping/docker,flavio/docker,rancher/docker,mtanlee/docker,ibuildthecloud/docker,coolljt0725/docker,laijs/docker,prertik/docker,jlebon/docker,asbjornenge/docker,konstruktoid/docker-1,crosbymichael/docker,mtrmac/docker,raja-sami-10p/moby,Ramzec/docker,AkihiroSuda/docker,qudongfang/docker,hypriot/docker,jwhonce/docker,thaJeztah/docker,ibuildthecloud/docker,maxamillion/docker,cpuguy83/docker,cyphar/docker,kunalkushwaha/docker,bearstech/moby,x1022as/docker,yp-engineering/docker,portworx/docker,dccurtis/docker,erikh/docker,mstanleyjones/docker,bonczj/moby-json-file-logger,johnstep/moby-moby,mahak/docker,afein/docker,thaJeztah/docker,ajaymdesai/docker,sfsmithcha/docker,ajaymdesai/docker,trebonian/docker,konstruktoid/docker-1,flavio/docker,jlebon/docker,tophj-ibm/moby,moby/moby,naveed-jamil-tenpearls/moby,rancher/docker,darrenstahlmsft/docker,lixiaobing10051267/docker,mtanlee/docker,thtanaka/docker,yosifkit/docker,paralin/docker,michael-holzheu/docker,hqhq/moby,rremer/moby,mixja/docker,splunk/docker,PatrickLang/moby,xiekeyang/docker,SvenDowideit/docker,PatrickLang/moby,YuPengZTE/docker,POLJM242/docker,msabansal/docker,darrenstahlmsft/docker,gnailuy/docker,lixiaobing10051267/docker,mkumatag/docker,bluebreezecf/docker,dims/docker,danyalKhaliq10p/moby,nawawi/docker,alfred-landrum/docker,dongjoon-hyun/docker,Mokolea/docker,ColinHebert/docker,zhuguihua/docker,mohmost12/docker,nalind/docker,cloudflare/docker,nawawi/docker,bearstech/moby,dsheets/moby,unclejack/docker,Syntaxide/docker,kunalkushwaha/docker,zhuguihua/docker,michael-holzheu/docker,fcrisciani/docker,afein/docker,jlhawn/docker,haveatry/docker,docker/docker,dongjoon-hyun/docker,lixiaobing10051267/docker,justyntemme/docker,harche/docker,raja-sami-10p/moby,konstruktoid/docker-upstream,Mokolea/docker,erikstmartin/docker,pramodhkp/moby,tophj-ibm/moby,noxiouz/docker,hqhq/moby,KarthikNayak/docker,harche/docker,cloudflare/docker,liaoqingwei/docker,kencochrane/docker,Mokolea/docker,gjaskiewicz/moby,danyalKhaliq10p/moby,ColinHebert/docker,xuxinkun/docker,mike1729/docker,catinthesky/docker,xuxinkun/docker,miminar/docker,jlebon/docker,wenchma/docker,konstruktoid/docker-upstream,rhatdan/storage,djs55/docker,dnephin/docker,q384566678/docker,YuPengZTE/docker,jvanz/docker,moul/docker,darrenstahlmsft/moby,coreos/docker,moypray/docker,twaugh/docker,moby/moby,JMesser81/docker,dsheets/moby,icaoweiwei/docker,thtanaka/docker,dperny/docker,laijs/docker,AkihiroSuda/docker,darrenstahlmsft/moby,shhsu/docker,moul/docker,michelvocks/docker,mtrmac/docker,amatsus/docker,stevvooe/docker,q384566678/docker,dnephin/docker,nalind/docker,PatrickLang/moby,AkihiroSuda/docker,bonczj/moby-json-file-logger,justyntemme/docker,maxamillion/docker,liaoqingwei/docker,tophj-ibm/docker,unclejack/docker,containers/storage,abhinavdahiya/docker,scotttlin/docker,cyphar/docker,kencochrane/docker,dims/docker,jimjag/docker,bluebreezecf/docker,kojiromike/docker,bonczj/moby-json-file-logger,tagomoris/docker,justincormack/docker,charleszheng44/moby,mixja/docker,KingEmet/docker,whuwxl/docker,tonistiigi/docker,raja-sami-10p/moby,jwhonce/docker,moby/moby,catinthesky/docker,dongjoon-hyun/docker,dnephin/docker,yasiramin10p/moby,gnailuy/docker,tmp6154/docker,lixiaobing1/docker,kojiromike/docker,asbjornenge/docker,noxiouz/docker,twaugh/docker,qudongfang/docker,shhsu/docker,tklauser/docker,jhorwit2/docker,brahmaroutu/docker,HideoYamauchi/docker,Morsicus/docker,dmcgowan/docker,mikedougherty/docker,diogomonica/docker,tklauser/docker,wenchma/docker,crosbymichael/docker,pradipd/moby,sarnautov/moby,dgageot/docker,mstanleyjones/docker,bluebreezecf/docker,haveatry/docker,gschaetz/moby,endophage/docker,estesp/docker,johnstep/moby-moby,ffoysal/docker,vdemeester/docker,konstruktoid/docker-upstream,ripcurld0/moby,qudongfang/docker,kolyshkin/moby,jhorwit2/docker,xiaods/docker,jwhonce/docker,Mokolea/docker,x1022as/docker,splunk/docker,yongtang/docker,kolyshkin/docker,13W/docker,eskaaren/docker,portworx/docker,laijs/moby