2.18.1
* Add xdg-user-dirs support, show Movies and Music directories
  in the file choosers
* Avoid crashes when we can't figure out a file's display name
  and we're adding it to the recent files list
* Make adding multiple files to a running Totem work again
* Misc build, bug and memory leak fixes
* GStreamer:
- Don't ask over and over when the user cancels a helper for a
  missing plugin
- Call the missing plugins helper when there's no video available
  and a subtitle was used
- Make the seek bar behaves properly when no soundcards are used
* Browser plugin:
- Remove rejection of streams based on mime-type, should allow
  playback of many more broken servers
- Make the wheel act properly on the volume button