Support for standard & smart XBMC Audio Playlists

[arigit]

Chorus already supports Custom Playlists, but lacks support of standard XBMC playlists for Audio.

Use case: I have a Smart Playlists that lists all albums that contain "Beethoven" in the Composer field, and another one for "Bach". XBMC, in "Music", has an entry for "Playlists" that shows all my playlists, where I can select one and then the matching albums are shown, from where I can play any or all. This is a request to have the same Playlist support in Chorus.