add force feedback :>

based on the rumble byte I've found in the GTA2 memory. This doesn't
seem to work well in multiplayer yet (or more generally, all the stuff
with message frames?) and there are still some custom rumble events not
implemented yet - see the wiki:
https://github.com/Bytewerk/gta2-hackers-remix/wiki/0x665770-Rumble-Byte