* Update PCSX2 to use the upstream AppImage.
* Complete PCSX2 standalone integration.
* Update volume controls to use mapped volume mode.
* Update GTK3 to build additional required bits.
* Update games to use .config/game/configs moving configurations out of the system config root.
* Split modules into a separate package (packages/misc/modules).
* Remove some unused packages and move a few virtual packages to packages/virtual.