[git] Gravity Trap bug

[grmblfzzz]

Got gravity trap on an archer in the Git version, and it does 0 dmg instead of the ~175 the tooltip says it should do. It still pulls people in, just doesn't do dmg. Made a debug rogue to see if it was isolated to archers, and the rogue had the same bug.

Also, for the record, Archers don't get Poison Gass trap from the maze. Probably good, as that leaves rogues still better at traps while Archers get the utility, just informing on the issue.