Sanity checking for zone disconnection.  I am dumb some days.
Merge pull request #3105 from SkyMarshal/airfixes

Sanity checking for zone disconnection.  I am dumb some days.
Quickfix for INFINIMEAT.
Merge pull request #3111 from Spamcat/master

MEATFIX
Merge pull request #3113 from Zuhayr/master

Firesuit icon fix.
Fixes #3106
Fixes #3118
Fixes #2921
Fixes #2421
Fix for destroying alien walls with your bare hands.
Merge pull request #3121 from Zuhayr/master

Alien resin wall fix.