Migrate replication controllers to generic etcd

pkg/registry/generic/etcd/etcd.go

@@ -241,6 +241,7 @@ func (e *Etcd) UpdateWithName(ctx api.Context, name string, obj runtime.Object)
 
 // Update performs an atomic update and set of the object. Returns the result of the update
 // or an error. If the registry allows create-on-update, the create flow will be executed.
+// A bool is returned along with the object and any errors, to indicate object creation.
 func (e *Etcd) Update(ctx api.Context, obj runtime.Object) (runtime.Object, bool, error) {
 	name, err := e.ObjectNameFunc(obj)
 	if err != nil {