Albums update

With V0.7 the catalog knows what album a track belongs to.

what’s new

• An album selector on music — narrow the catalog down to one release.
• ?album= is shareable, and back/forward moves between selections.
• Album names sit under each track title, and on the track page under the title.
• Playing while an album is selected keeps the queue inside that album, in running order. Play from All or anywhere else and you get the whole catalog, shuffled.