adds support for plugin requests that get a response callback
add plugin events
Responses and plugin events no longer need to be Events

Events have extra data on them which we shouldn't pass along
Merge branch 'feature-plugin-requests' of github.com:gameclosure/native-android-priv into develop

* 'feature-plugin-requests' of github.com:gameclosure/native-android-priv:
  Responses and plugin events no longer need to be Events
  add plugin events
  adds support for plugin requests that get a response callback

Conflicts:
	native-core