Allow Kube proxy to watch for service/endpoint changes

Expose `GET /endpoints/<serviceName>`.  Allow watch on endpoints and with services with `fields=Name%3D<serviceName>`
Do we really want to allow this case? I feel like if you add in a path to the host name, you probably had a good reason and we shouldn't ignore it? Or we should error out. Silently pretending you didn't add a path seems bad.