[Request] Restore layers to default at shutdown.

[ReyVGM]

Currently, if you disable a background/sprite layer and close the emulator, then open it again—the graphic layers are still disabled.

This can get a bit confusing if you come back to the emulator hours or days later and wonder why all the graphics are missing.

So I request for the layers to go back to default if the emulator is closed. It's possible there's someone out there that wants this option as default, so maybe a toggle could be added for the ones that don't want this behavior as default?

I tested it with the Genesis and SNES core.

[YoshiRulz]

This is because they're sync settings. edit: as opposed to cheats, I mean

Maybe my idea for #3091 would help? Some sort of reset-on-exit? I suppose you could set that up with the current ad-hoc system too, it would just be a lot of duplicate code.

[nattthebear]

This is because they're sync settings.

Non-sync settings are saved to config as well