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>`
`127.0.0.1` is interpreted as a path when you convert it to a URI, rather than the host/port value.  I'll change it to do the parse first, check whether scheme is set (i.e., did we find a real URL), and if not treat base as a host-port with optional path value.