Persist following properties:
mopidy.core.tracklist
_tl_tracks
_next_tlid
get_consume()
get_random()
get_repeat()
get_single()
mopidy.core.history
_history
mopidy.core.playlist
get_current_tl_track()
get_time_position()
mopidy.core.mixer
get_volume()
Details:
- moved json export/import write_library()/load_library() from mopidy/local to mopidy/models
- new core methods save_state(), load_state()
- save_state(), load_state() accessible via rpc
- save state to disk at stop
- load state from disk at start
- new config: core.restore_state ("off", "load", "play")
TODO:
- seek to play position does not work. Timing issue.
- use extra thread to load state from disk at start?
