Automatic merge from submit-queue (batch tested with PRs 36990, 37494, 38152, 37561, 38136)
api federation types
First commit adds types that can back the kubernetes-discovery server with an `kubectl` compatible way of adding federated servers. Second commit is just generated code.
After we have types, I'd like to start splitting `kubernetes-discovery` into a "legacy" mode which will support what we have today and a "normal" mode which will provide an API federation server like this: https://github.com/kubernetes/kubernetes/blob/master/docs/proposals/federated-api-servers.md that includes both discovery and proxy in a single server. Something like this: https://github.com/openshift/kube-aggregator .
@kubernetes/sig-api-machinery @nikhiljindal
f600c94eab