Make sort orders configurable

Sorting is currently very primitive in Noise. It could be improved by providing the option to sort based upon metadata, as is found in players such as iTunes. The MusicBrainz page linked details the tag reference spec. Personally speaking, I think albumartistsortorder, artistsortorder, originaldate and possibly albumsort would be definitely worth supporting. Where no tag data is found, those entries could be appended to lists in the existing manner.