Split ResourcefulApi

[eFrane]

This class tries to do to much. It simultaneously handles the json:api specific request/response wrapping/unwrapping and acts as a container for resource specific actionable route methods.

An idea might be to split the request/response handling into a JsonApi class. Additionally, the route methods handling should be rewritten to be a lot less magical. I don't have a concrete plan for that at the moment though.

[eFrane]

Pondering on, most of the request processing done in ResourcefulApi could probably just be pushed up into Api.