Should fix gearboxes breaking after changing their type to another with the same model.
Updated Engine Volume

Engine volume now ramps up with rpm, in addition to throttle.
Existence check around the extra gun list.
More verbose errors in muzzleflashes, can't pinpoint it right now.
Merge remote-tracking branch 'remotes/upstream/master'

Conflicts:
	lua/autorun/acf_globals.lua
Merge branch 'master' of https://github.com/Bubbus/XCF