Add copyright notice
Change some ridiculous strings
Fullscreen enhancements

 - Save window size during fullscreen
 - Fullscreen on alt-enter as well (F11 would require another override
   and callback)
Use threads for audio callbacks

PulseAudio really doesn't like it when our signal arrives while it's
still processing the previous audio.  To avoid crashes and deadlocks,
use separate threads and a lock to avoid concurrent access.
Static declarations
Silence callback warning
Update scripts