Update the go server api controller template to return the Router interface instead of the api specific router.
The Router interface type has the Routes function, which is what the generated `NewRouter` function needs. (not the api specific interface).
* Enhance go api server with interfaces router binding and services
Enhance the default go api server generation to define interfaces for an API's routes and services. Handle an endpoint's http binding in the generated router and the skeleton for the service logic in an API service.
* Include interface documentation in Go Server generation.
