Like Delete, which can now run over multiple types:
kubectl delete pods,services -l name=foo
Get should be able to span items for label selection
kubectl get pods,services -l name=foo
When a CLI command `kubectl get rc --api-version=v1beta3` is called,
the API resource name should match v1beta3, not whatever the default
RESTMapper version is. This allows the correct resource name to be
returned ("replicationcontrollers", instead of "replicationControllers").