kube-dns addon optional so that users can deploy their own DNS solution. ([#57113](https://github.com/kubernetes/kubernetes/pull/57113), [@wwwtyro](https://github.com/wwwtyro))

* `kubectl port-forward` now supports specifying a service to port forward to, as in `kubectl port-forward svc/myservice 8443:443`. Additional support has also been added for looking up targetPort for a service, as well as enabling using svc/name to select a pod. ([#59809](https://github.com/kubernetes/kubernetes/pull/59809),...