Destroy() cleanups in VOREStation code

* Remove remaining hard del()'s in our code.
* Replace deleted() and gcDestroyed with QDELETED macro.
* Fix some strange calls directly to Del() (capital D)
* Make Destroy() return qdel hints.
* Make a few of the Destroy()'s more comprehensive in cleaning up references.
* In edited Destroy() procs, converted to use qdel_null and qdel_null_list macros when possible for pretty code.
* Removed unused variable `sleevecard`

code/game/objects/structures/crates_lockers/closets/egg_vr.dm

@@ -16,7 +16,7 @@
 /obj/structure/closet/secure_closet/egg/attackby(obj/item/weapon/W, mob/user as mob) //This also prevents crew from welding the eggs and making them unable to be opened.
 	if(istype(W, /obj/item/weapon/weldingtool))
 		src.dump_contents()
-		del(src)
+		qdel(src)
 
 
 

code/game/objects/structures/railing.dm

@@ -29,9 +29,10 @@
 		update_icon(0)
 
 /obj/structure/railing/Destroy()
-	for(var/obj/structure/railing/R in oview(src, 1))
+	var/turf/location = loc
+	. = ..()
+	for(var/obj/structure/railing/R in orange(location, 1))
 		R.update_icon()
-	..()
 
 /obj/structure/railing/CanPass(atom/movable/mover, turf/target, height=0, air_group=0)
 	if(!mover)

code/game/objects/structures/trash_pile.dm

@@ -237,7 +237,7 @@
 	if(!path) //Tapped out, reallocate?
 		for(var/P in allocated_gamma)
 			var/obj/item/I = allocated_gamma[P]
-			if(!I || istype(I.loc,/obj/machinery/computer/cryopod) || I.gcDestroyed)
+			if(QDELETED(I) || istype(I.loc,/obj/machinery/computer/cryopod))
 				allocated_gamma -= P
 				path = P
 				break