for(var/bad_code in world)

Removes a very large amount of world loops.
Adds a macro to painlessly generate a global list, and the needed code to modify the list when an object is made or deleted automatically.
Cleans up some commented out code.

code/modules/maps/tg/reader.dm

@@ -285,7 +285,7 @@ var/global/use_preloader = FALSE
 		var/atom/instance
 		_preloader.setup(members_attributes[index])//preloader for assigning  set variables on atom creation
 		var/atype = members[index]
-		for(var/area/A in world)
+		for(var/area/A in all_areas)
 			if(A.type == atype)
 				instance = A
 				break