spotify collection post mid-term TODO

[Bart Cerneels]

* SpotifyCollection Object only created if Controller status is OK and
general initialization workflow
* Download resolver binary from kollide from settings dialog
  * Pass API key on build, shepherd changes into resolver repo.
* Controller GPLv3 issue -> get an exception from Leo and Muesli or
we'll have to relicense the Amarok codebase (not likely because of
GPLv2 only files).

extra's (likely post GSoC)
* PlaylistProvider for user's own spotify playlists (which can be
shown in the "Saved Playlists" a.k.a. UserPlaylists category).