Implemented shuffle and repeat

Major changes are
* Changed now playing full layouts to include buttons for shuffle and repeat,
  and to handle different screen sizes better.
* Introduced our own media controller styles, which gives the app a more
  modern apearance, even on older devices.
  It's a holo dark style, with a list selector (which was missing), but no
  hardcoded width.
* Shuffle and repeat status are included in the play status broadcast, and the
  playing status is extended to handle the three valued enum play/pause/stop.
* Squeeze service changed to more accurately monitor the players state.
* The communication strategi between the service and the activities is changed
  to minimize communication, by providing and using the data the UI needs in
  the callbacks.
* Use fade-in-secs (setting) when going from pause to play.