6.4.4

1. Allow service specific custom actions - thanks to crystalgipsy.
2. Fix add/play all for 'spoton' - thanks to stiefenm.
3. Only update lyrics times, etc, if displayed track is current track.
4. Only highlight lyrics line and auto-scroll if set to sync MAI view with current track.
5. Fix 'Scroll for more' showing where it should not.