Music: Add composer support.
dmix: Code style.
item: When Android specific, abstract the class.

This refactors the work from 3fdfe1b in a more sensable way, so Android code
can cleanly be added as necessary.

This should make adding Android specific code to JMPDComm cleaner.
Item: Don't crash when a translation doesn't exist for Unknown*.
Jump to beginning of current song instead of previous if more than 5 sec have been played
Collapsed Albums: add setting
Collapsed Albums: add strings

Conflicts:
	MPDroid/src/main/res/values-de/strings.xml
Collapsed Albums: add PlaylistAlbum
Collapsed Albums: add size() and hasText() to AbstractPlaylistMusic
Collapsed Albums: add CollapsedPlaylistFragment
Collapsed Albums: use CollapsedPlaylistFragment
make playlist text autoscroll
make header in SongsFragment autoscroll
make Songs in SongsFragment autoscroll
autoscroll in albumfragment -- partially

Conflicts:
	MPDroid/src/main/java/com/namelessdev/mpdroid/views/AlbumDataBinder.java
show disc and track number in NowPlaying