rpctypes: test error equivalence with Error()
rpctypes: test error equivalence with Error()

grpc.Errorf() now returns *rpcError, which makes comparisons shallow.

swingbach/etcd,endocode/etcd,handsomesun/etcd,sebrandon1/etcd,jonboulle/etcd,cockroachdb/etcd,tguangch/etcd,xiang90/etcd,insequent/etcd,visheshnp/etcd,joshix/etcd,ravigadde/etcd,luxas/etcd,mickep76/etcd,handsomesun/etcd,etcd-io/etcd,glycerine/etcd,tguangch/etcd,sinsharat/etcd,a-robinson/etcd,ajityagaty/etcd,glycerine/etcd,armstrongli/etcd,yudai/etcd,ajityagaty/etcd,zaphod-concur/etcd,bdarnell/etcd,xiang90/etcd,qqsun8819/etcd,ktateish/etcd,rchicoli/etcd,coreos/etcd,qqsun8819/etcd,jlamillan/etcd,cockroachdb/etcd,etcd-io/etcd,OyTao/etcd_learning,sinsharat/etcd,akauppi/etcd,jlamillan/etcd,CrazyJvm/etcd,YuleiXiao/etcd,li-ang/etcd,mkumatag/etcd,heyitsanthony/etcd,akauppi/etcd,jonboulle/etcd,rnaveiras/etcd,lorneli/etcd,bdarnell/etcd,nekto0n/etcd,purpleidea/etcd,mqliang/etcd,glevand/coreos--etcd,fanminshi/etcd,plasticbox/etcd,plasticbox/etcd,whuwxl/etcd,CrazyJvm/etcd,mkumatag/etcd,hongchaodeng/etcd,sebrandon1/etcd,hongchaodeng/etcd,etcd-io/etcd,coreos/etcd,armstrongli/etcd,linuxcer/etcd,ravigadde/etcd,nekto0n/etcd,mickep76/etcd,gyuho/etcd,ktateish/etcd,mqliang/etcd,insequent/etcd,gyuho/etcd,lumjjb/etcd,swingbach/etcd,a-robinson/etcd,zaphod-concur/etcd,YuleiXiao/etcd,joshix/etcd,glevand/coreos--etcd,purpleidea/etcd,vimalk78/etcd,endocode/etcd,rnaveiras/etcd,luxas/etcd,bluebreezecf/etcd,mkumatag/etcd,vimalk78/etcd,OyTao/etcd_learning,yudai/etcd,whuwxl/etcd,rnaveiras/etcd,visheshnp/etcd,ajityagaty/etcd,heyitsanthony/etcd,rchicoli/etcd,fanminshi/etcd,lorneli/etcd,dannysauer/etcd,dannysauer/etcd,mqliang/etcd,linuxcer/etcd,li-ang/etcd,lumjjb/etcd,bluebreezecf/etcd