Add remoting options to server/config.json

/to @bajtos @ritch 

See https://github.com/strongloop/loopback/issues/608
See https://github.com/strongloop/loopback/pull/337
The general approach is to keep the templates as small as possible and implement most features in loopack. That way we can roll bugfixes without having to ask the users to upgrade the generated code.

AFAIK, `loopback.rest` has access to the `app` object it is mounted on, thus it can read `app.get('remoting')` itself, there is no need to pass it down from here.