add a zombification chem to the traitor poison bottle pool

[poland spring]

I think this would lead to zombie rounds every round

considering this is the biggest criticism I could see for this idea I'll just reiterate what others have said, specifically that this should be in traitor poison bottles. that way it won't happen every round and although it might suck on low pop servers so do 90% of all the other "kill people" traitor items. i just really really want to have poisons do more interesting things than just do oxy/tox/whatever damage, we need more death chems that are actually INTERESTING to use