Add a simple "autoconfigure" facility for input devices, that lets the user choose
if several are connected.
Can be expanded in the future to provide custom default mapppings for various devices as long as we manage to identify them.
Ideally, key mappings should be unique per device but they aren't yet.
-File -> Savestate Slot: Lets the user pick the savestate slot to be used.
-Game Settings -> More Settings...: Opens the main settings screen from anywhere.
-Game Settings -> Control Mapping...: Opens the key mapping screen from anywhere.
-Infrequently changed options were removed.
-Organised menus; nothing is out of place anymore.
-Simplified menus: as some options were removed or moved, it's easier to find what you're looking for, now.
