SPI/VACOPS doodles

on account of someone else's image of a couple Spartans drifting in space, one of whom was wearing SPI Armor, which isn't meant for it. Decided VACuum OPerationS variant isn't worth it. Main reason: Part of SPIA's stealth system is thermal; that is, it cools itself to hide emissions from the wearer, matching with ambient temperature. Problematic enough in atmosphere; much more so in space, since you don't really have "ambient"... Be different on each side (if near a star)... thrusters be immediate give away...

added thrusters, additional heat sinks...