Patched holes in SoftDelete that were causing null reference errors.
Fixes #3892
Tweaks the zone rebuilding logic to prevent doors being ignored.
Fixes #4046
RCDs no longer create plating with air on it.
Fixes #3545
Mining fixes as it was annoying as fuck.  Also a random object with nothing in it removed.
Some turf cleanup and the like.  Trace gases are now properly handled by ZAS on world load.
Fixes #2485
Tradeband and Gutterspeak now have a different font than Tradeband.
Fixes #4143
Reverts some geometry code to a functional state.
Fixes #4045
Merge pull request #4245 from SkyMarshal/airfixes

Lots of bugfixes.