Major changes in 3.16.1:
- Loads of performance fixes, related to thumbnailing
  when a video is playing
- Fix (again) doubling files added on the command-line
- Don't monitor the tracker source, it adds incomplete
  items to the view
- Fix Videos icon not showing in volume control
- Provide a symbolic variant of the app icon
- Fix frames not getting applied for new thumbnails
- Don't warn when video rotation is unset