Only drop temperature in tropical biomes during mid wet season if the default temperature is hot
Change default altitude modifiers values so that it's enabled by default
Changed canSeeSky checks to use motion blocking heightmap instead
Increased thermoregulator fuel time, tweaked water purifier GUI texture
Implemented the thermoregulator. Closes #805, #726
Adjusted determination of passable blocks for temperature filling
Implemented F3+7 debug combo