New Playlist Permalinks

- Permalinks for playlists now include the playlist type( see #1 ):
http://somesite.com/playlist/audio/some-playlist

- Playlist archives can now be filtered via the type:
http://somesite.com/playlist/audio/
http://somesite.com/playlist/video/
http://somesite.com/playlist/

- Links in the media columns now launch to a new tab/window