Lowering RPM on guns does not effect gun costs

[Tox00]

A component of cost I found out was RPM effects cost, I wish to lower the cost of one of my vehicles by lowering its RPM and other parts, but lowering RPM currently does not effect point cost.

[Ally-for-Hire]

damn, looks like i missed wired RPM, this should be a quick fix

[Ally-for-Hire]

Addressed by #252