More potential NPE protection. (Getting some annoying NPE in the emulator which points to this code. Updated version number as well
Added support for more music players:

- Spotify (via the notification listener service)
- Player Pro & Player Pro trial
- Rdio
- Doubletwist
- Rocketplayer & Android Muic Player
- Samsung (untested)
- Rhapsody (untested)
- MIUI (untested)
- HTC (untested)

* Attempt to fix cursor leak.
Merge branch 'master' of https://github.com/timusus/MuzeiMusicExtension