remove the sub-area system

Removes area/list/related and area/master.
They were only used by the old lighting subarea system.

Signed-off-by: Mloc <colmohici@gmail.com>

code/modules/hydroponics/spreading/spreading.dm

@@ -6,10 +6,9 @@
 		var/list/turf/simulated/floor/turfs = list() //list of all the empty floor turfs in the hallway areas
 		for(var/areapath in typesof(/area/hallway))
 			var/area/A = locate(areapath)
-			for(var/area/B in A.related)
-				for(var/turf/simulated/floor/F in B.contents)
-					if(!F.contents.len)
-						turfs += F
+			for(var/turf/simulated/floor/F in A.contents)
+				if(!F.contents.len)
+					turfs += F
 
 		if(turfs.len) //Pick a turf to spawn at if we can
 			var/turf/simulated/floor/T = pick(turfs)
@@ -256,4 +255,4 @@
 		die_off()
 
 /obj/effect/plant/proc/is_mature()
-	return (health >= (max_health/3))
+	return (health >= (max_health/3))