Replace global all_areas list with world.

It ends up having similar performance, so might as well not bother with all_areas.

code/game/gamemodes/cult/hell_universe.dm

@@ -54,7 +54,7 @@ In short:
 
 
 /datum/universal_state/hell/proc/AreaSet()
-	for(var/area/A in all_areas)
+	for(var/area/A in world)
 		if(!istype(A,/area) || istype(A, /area/space))
 			continue
 

code/game/gamemodes/endgame/supermatter_cascade/universe.dm

@@ -84,7 +84,7 @@ The access requirements on the Asteroid Shuttles' consoles have now been revoked
 		return
 
 /datum/universal_state/supermatter_cascade/proc/AreaSet()
-	for(var/area/A in all_areas)
+	for(var/area/A in world)
 		if(!istype(A,/area) || istype(A, /area/space) || istype(A,/area/beach))
 			continue
 

code/game/gamemodes/events.dm

@@ -169,7 +169,7 @@ var/hadevent    = 0
 
 
 	var/list/area/areas = list()
-	for(var/area/A in all_areas)
+	for(var/area/A in world)
 		if(istype(A, /area/security/prison) || istype(A, /area/security/brig))
 			areas += A