avoid floating point desync, other script tweaks

So. A while ago, while trying to prevent hogs blowtorching getting turned around, unc0rr altered the old range of blowtorch from 1/8th of 180° up or down, to a 4° gain in upwards and a -4° loss in downwards. He also made it so that starting tunnels could fail to erase sufficient terrain, trapping hogs. Here are a couple of workarounds to more closely approximate old behaviour (do some initial erasure, adjust min/max angles)

Safety check. The main place this can be a problem is on a mild bowl w/ multiple hogs. Could possibly add a hog collision check in here.

split version information in engine too