Moved network related code into com.lastcrusade.fanclub.net package

Added SingleFileAudioPlayer, PlaybarFragment, MediaStoreWrapper, and
TestPlaybarActivity for development and testing of the playbar (the bar at the
bottom of the app).
    Currently, this will respond to a play request by playing the first song on
the phone.
    Next steps are to look at how we queue music, and whether the interface
callback is the right approach