Fixes #45 - Exposes resource instance context on interceptor callbacks to allow custom field cleanup interceptor

Added after response interceptors to be able to define custom callbacks that execute on all resources after method completion.
Upgraded Karma to 0.10
Removed $ default exclusion setting since AngularJS automatically excludes keys starting with $ in their toJson
Merge pull request #48 from tpodom/master

Adding after response interceptors and exposing resource instance context to before response interceptors