Auto add tracks from album/artist; add new spl

- Added ability for dash and web to update settings
- Added ability to automatically add all tracks from current album or
all tracks from current artist to shuffle playlists
- - Made this work for local tracks by creating a function that gets the
uris for the artist, all their albums, and all tracks on those albums,
all of which are added to the shuffle playlists
- - - will look into way to scope this to single album with no album in
the search terms
- Added ability to automatically create new shuffle playlist is the
others are full.
- - This also automatically creates the Shuffle Playlists folder and
places this new (and sequentially named) shuffle playlist at the end of
that folder
- - - I can now re-order all user playlists at will from the spapp. Look
into sorting utility
- - both folder name and shuffle playlist base name are customizable in
settings