Reagent balancing

Reagent Rebalancing

-Reduces the Overdose threshold from 90 to 30
-Removes Overdosing from nearly all reagents except painkillers
-Increases the depletion of a lot of previously long-lasting medical chems
-Dramatically increases the depletion rate of painkillers
-Removes the "mildly toxic" var from a lot of reagents (Bay doesn't even use this anymore)
-Fixes a few overdose/OVERDOSE definitions
-Makes anti-toxin actually purge a few nasty reagents
-Rebalances the tox/rad damage of a few toxic chems
-Adds in Hellwater ( adminbus reagent)

The increased depletion rate effectively means that the chemist will have something to do for far longer into the round than to just make X, Y, and Z during the first 10 minutes of the game and faff off for the rest of the round.