Various bugfixes

Fixes for: 
#3482
#2469
#3928
#3863
#3769
In airlock/New() airlocks across all zlevels are added to list/portals so I made a new global list called airlocks and added them to that instead. After putting this in, I didn't teleport to other zlevels when running through portals after about 20 or 30 test jumps. 

It only seems to be used for a malf ability, so there might actually be a separate exploit style issue there with malf AIs messing with doors on CentComm.