concurrency: expose leader revision and proclaim headers for election
concurrency: expose leader revision and proclaim headers for election

mickep76/etcd,cockroachdb/etcd,whuwxl/etcd,bluebreezecf/etcd,mqliang/etcd,mickep76/etcd,vimalk78/etcd,li-ang/etcd,mqliang/etcd,sinsharat/etcd,coreos/etcd,sebrandon1/etcd,vimalk78/etcd,armstrongli/etcd,cockroachdb/etcd,yudai/etcd,lorneli/etcd,akauppi/etcd,mkumatag/etcd,rnaveiras/etcd,ajityagaty/etcd,glevand/coreos--etcd,yudai/etcd,etcd-io/etcd,xiang90/etcd,mkumatag/etcd,li-ang/etcd,tguangch/etcd,bdarnell/etcd,gyuho/etcd,xiang90/etcd,mqliang/etcd,etcd-io/etcd,ajityagaty/etcd,akauppi/etcd,mkumatag/etcd,sebrandon1/etcd,YuleiXiao/etcd,tguangch/etcd,bdarnell/etcd,plasticbox/etcd,YuleiXiao/etcd,bluebreezecf/etcd,sinsharat/etcd,whuwxl/etcd,visheshnp/etcd,gyuho/etcd,heyitsanthony/etcd,a-robinson/etcd,coreos/etcd,plasticbox/etcd,armstrongli/etcd,heyitsanthony/etcd,visheshnp/etcd,a-robinson/etcd,dannysauer/etcd,lorneli/etcd,ajityagaty/etcd,rnaveiras/etcd,fanminshi/etcd,joshix/etcd,etcd-io/etcd,rnaveiras/etcd,fanminshi/etcd,joshix/etcd,glevand/coreos--etcd,dannysauer/etcd