Added indicator to progress bar
First attempt at asyncronous loading of music
Mostly implemented asynchronous music loading
loading indicator now turns off if next is hit multiple times
Fixed bug that causes undefined behavior when cleaning the playlist
Changed the tired menu option to operate on selected song
Changed the way playlists are cleaned. The isDirty method returns an index set of dirty songs. The index set is used to update the table view, then cleanPlaylist should be called. Attempts have been made to only update changed rows. Also, table edits are now animated.
Fixed issue where clicking on disabled song skipped the next viable song.
Added indicator to song tab, and fixed problem that caused lyrics to stop loading
Merge branch 'dev' of https://github.com/cjfman/Pandora-s-Box into dev

Conflicts:
	Pandora's Box/en.lproj/MainMenu.xib
Merge branch 'async' into dev