Allow sorting artists list by more criteria

It would be great to be able to sort the artists list by:

• album number
• recently played

Album number is easy to do (I can also do that by number of tracks if you want)

Regarding recently played, I suppose that means sorting by tracks last played date, which might be a bit costly, but it should be doable.

(I can also do that by number of tracks if you want)

I do.

assigned to @chouquette

changed milestone to %0.10.x

closed with commit 5261a3c7

closed with merge request !488 (merged)