Tweaks

Tweaks (minimal configurations to make a game functional) can be installed (to /usr/share/tinkergame/tweaks) from the optional external repo tinkergame-tweaks.

If a game tweak is found in this directory, tinkergame loads that tweak before starting the game and opens a Notifier.

Support for user-defined tweaks is still built in, but it is unlikely to be worth any documentation.