Fixes wrong ignite adminlog message when clicking plasma airlock with hand.
Fixes checks during welding of closets, walls, mineral walls, airlocks.
simplifying thermite ignition code on walls. Fixes being able to move around while deconstruction procedures of rwall(replacing sleep() with do_after() ).
Simplifying code and fixing inconsistency with slicing diamond wall ( weldingtool faster than drill/cutter at slicing diamond wall )
missing "return"
Merge branch 'master' of https://github.com/tgstation/-tg-station into plasmadoorfix

Conflicts:
	code/game/machinery/doors/airlock.dm
Fixing mistake so Travis can compile.
Merge pull request #5081 from phil235/plasmadoorfix

Plasma airlock & wall slicing fixes