Buffed cryo's cooling power to make up for oversight.

Created by: DrCelt

Huh. That's pretty cool actually. Turns out the reason wasn't because of me nerfing anything that does cold damage, but rather nerfing heat loss to the environment, and cryo is effectively just a fancy environment apparantely. Luckily there's already code in here to pick up the pace when cryo's environment isn't up to scratch. fixes #8052 (closed)