Map: Toxins update

(To master!)

Some scientist cronies were bemoaning that toxins this map was simply awful, for tons of reasons. No ways to mix out the now incredibly high and ruining carbon in a mix, the vent/injector had amount of pipe that would always pull stuff out, etc.

So, I did some changes. In actuality they are fairly minor and merely functionality updates. It isn't even the best it could be, but that ended up being a more purposeful thing. A scientist can beg Atmos for more, maybe. Still, this will easily get those poor bomb makers by.

A complaint is the pumps don't look entirely right, but that isn't something that can be fixed. Additionally, the wall mounted igniters ought to be somewhere else, but to be honest I could not be assed with spending half a hour fiddling with the often-arbitrary direction flag. Still, it functionally works.

It was also actually tested in practice this time, cuz I was helpfully told how to actually make a worldfile to do so. Evidently I kept cleaning it up.