Added a script which does all the same things as the Debian MATE XSS script did…
Installs the Full XScreenSaver collection (GL + Extras)
Removes MATE Screensaver
Symlinks XSS commands to replace MATE SS commands
Optional SETUID for Sonar
Ensures MATE SS doesn’t try to reinstall
Locking works via “System” –> “Lock Screen”
Fix for locking via keyboard shortcut