EloquentController does not need to extend JsonApiController

[lindyhopchris]

There is little benefit to EloquentController extending JsonApiController, particular as the EloquentController is not using any of the method signatures such as $resourceId. It would make more sense to combine standard controller helpers into a trait and use this in both EloquentController and JsonApiController.

This would also make it easier for people to write their own controllers as they could then just apply the trait if for some reason the method signatures of JsonApiController cannot be used. An example of this is when using wildcard sub-domains, each method on that controller would actually get called with the sub-domain variable first so JsonApiController would not be easy to use.

[lindyhopchris]

This change is no longer required because the changes for Laravel 5.3 mean the Eloquent controller needs to use the constructor in the JSON API controller, plus now needs to use the same method signatures for each of the action methods.