Updated a bunch of places so they use IsAdvancedToolUser().
Updated a bunch of "You don't got the dexterity!" messages with consistent span classes.

Added PASSTABLE flag for keepers, plus obj/turf vision.
Adds universal_speak, though they still can't talk outside of binary chat.
Removes atmospheric damage from keepers.
Adds keeper cannibalism.

Did something with gun sprites?? No idea what but it's probably awesome.