Orderable replacement spacesuits for vox, plasmamen, and greys

Created by: Skullyton

Adds a spacesuit that should only be wearable by greys. (Sprites courtesy of Niggly)

Also adds supply crates to cargo that provide internals and spare assistant space suits for Vox, Plasmamen, and Greys (Not that they need spare internals, but it's a way to get the grey spacesuit in)

I've put the cost at 100 credits in case of balance issues, unless there's enough of an argument as to why they should either be cheaper or more expensive.

Grey spacesuits can't use large oxygen tanks in the exosuit slot, only emergency-sized tanks and flashlights, so you'd have to sacrifice your backpack slot if you wanted to go spacewalking with a decent-sized tank, or just get a better spacesuit.