Merge pull request #3458 from Baystation12/dev

Dev
Fix for #3460.
Doublesuperheating fix.
Merge pull request #3461 from Segrain/dev-freeze

Dev-freeze bugfixes.
Made the vox shuttle bridge free of oxygen.
Added nitrogen tanks for pressure cannons.
Fixing a custom item.
Added a knife harness/duelling knives.
Made dispensers unwrenchable.
Added some appearance data back to monkey variants.
Fixed the order of update/return statements for dispenser.
Merge pull request #3464 from Zuhayr/feature

Fixes, duelling knives.
Merge branch 'dev' of https://github.com/Baystation12/Baystation12 into dev