Sideports a couple of init unit tests from Neb. (#7893)

* Sideports a couple of init unit tests from Neb.

* Trying to unfuck initialize logic.

* Removing del()s.

* Adjusting return values to Initialize().

* Moving some dangerous object logic from obj onto the two types that use it.

* Rolling back some init changes and commenting out initialized atom unit test.

* this comment formatting is a minor war crime

* Removed sleep() from signaler circuit Initialize().

* Additional Init fixes post-rebase.

* Uncomments subsystem test since that's passing.

code/game/objects/structures/crates_lockers/__closets.dm

@@ -37,7 +37,6 @@
 
 /obj/structure/closet/Initialize()
 	..()
-	// Closets need to come later because of spawners potentially creating objects during init.
 	return INITIALIZE_HINT_LATELOAD
 
 /obj/structure/closet/LateInitialize()