travis.yml: remove "./cmd"
travis.yml: remove "./cmd"

Signed-off-by: Gyuho Lee <3454051ee3341eb69bdf6fca40899cdad4d86496@gmail.com>

xiang90/etcd,heyitsanthony/etcd,vimalk78/etcd,gyuho/etcd,coreos/etcd,li-ang/etcd,xiang90/etcd,rnaveiras/etcd,fanminshi/etcd,bdarnell/etcd,fanminshi/etcd,rnaveiras/etcd,mkumatag/etcd,coreos/etcd,joshix/etcd,etcd-io/etcd,etcd-io/etcd,cockroachdb/etcd,lorneli/etcd,etcd-io/etcd,ajityagaty/etcd,mqliang/etcd,sinsharat/etcd,heyitsanthony/etcd,dannysauer/etcd,vimalk78/etcd,sebrandon1/etcd,mkumatag/etcd,bdarnell/etcd,sebrandon1/etcd,ajityagaty/etcd,mqliang/etcd,gyuho/etcd,ajityagaty/etcd,rnaveiras/etcd,whuwxl/etcd,whuwxl/etcd,li-ang/etcd,dannysauer/etcd,glevand/coreos--etcd,glevand/coreos--etcd,cockroachdb/etcd,mkumatag/etcd,joshix/etcd,mqliang/etcd,lorneli/etcd,sinsharat/etcd