Removes old/unused code from the tree. Use version control if you need it for some reason.
Merge remote-tracking branch 'remotes/upstream/master' into Common_comms_MicOff

Conflicts:
	_maps/map_files/MetaStation.v39K.dmm
	_maps/map_files/tgstation.2.1.3.dmm
Fixed teleporter icon not updating properly

Related to power change problems so why the hell not
fixes fuel tank crate
replaces firelocks
Full tile window placing on grilles
Fixes flashes being useless
shuttle windows
Fixes chem grenade phasing through windows/windoors. Changes chem grenade reactions to be slightly more realistic, volume-wise.
windows damage and such
added window repairing
adds help intent check for repairing windows
fixed metastation, fixed basic window having no icon state
Hud rewrite rewrite. Now datum-based and somewhat generic.
health tweak to be additionally rounded
buffs defibrillator PNR to 5 minutes
makes doors infinitely better
dangerdoors
Updates files for door closing
tweaks airlock closing proc calling