Major changes in 3.3.3 are:
* Implement the org.freedesktop.FileManager1 DBus interface
* Show context menu for current folder when clicking empty space
  in list view
* Sort XDG dirs in the places sidebar according to the current locale
* Fix handling of Ctrl+T on the desktop window
* Fix icon view wrap-around key navigation
* Fix rubberband scrolling in maximized windows
* Fix a crasher when closing a window
* Don't use deprecated GLib and GTK functions