(Check these up!) Pistols & modular-weapon

I've had the handguns on hold for a while, but thought I'd dust 'em off and see about implementing the Leadworks modular weapon system.

Much of the detail is in the individual commit messages, and the modular guns should really get some practicality/sanity-checking from our IRL shooters as I'm not one myself.  In particular, I'd appreciate any thoughts on the inclusions/not and whether you think something else might work better.  (That said, there's no noise-designation for guns, so I can't include an integral suppressor or muzzle brake.  Otherwise, I would.)

If you like what you see (or don't, but think it can be fixed!), let me know and I'll whip up the rest of the mod-gun gear & make the fixes.  Just wanted to get this off the shelf and operational.