feat(XbmcService): implement the XbmcService a WebSocket connection to XBMC

XbmcService provides a WebSocket connection to XBMC. This allows us to have continuous
bi-directional communication with XBMC so we can send JSON-RPC requests, receive responses and
receive notifications from XBMC when things change (i.e. a movie is added).
feat(movies): create a basic implementation for the movies section

This is a basic implementation that does the following:
* Lists all the movies in the library.
* Listens for movie specific VideoLibrary.* notification.
* Updates the movie list for VideoLibrary.onRemove and VideoLibrary.onUpdate notification.
* A filter for converting XBMC image urls.