VV Refactor

Ports /tg/'s VV refactor. Most of this is just cleaning up and making it
easier on the coders, but everyone else benefits too:

 - Mass mod no longer freezes the server (CHECK_TICK <3)
 - Attempting to change any of the step_* values or anything that will
 otherwise disable pixel movement will now prompt you and ask if you are
 sure you want to continue
 - You can actually enter |text| again in a box, rather than being
 forced to always use the multi-line input
 - Cookies! VV saves your search and scroll position for a given UID,
 rather convenient for debugging
 - The refresh button on /clients works finally
 - You can view lists in detail by clicking on them like any other
 reference, and edit them directly that way. This also means there is no
 hard limit on how many variables you can see in a list before it's
 truncated- it will just be hidden until you view the list in VV
 directly.
 - You can shuffle lists and clear duplicate/null entries.
 - Mildly reordered the stuff in the dropdown, inconvenient but
 necessary.

code/game/objects/items/weapons/power_cells.dm

@@ -28,13 +28,14 @@
 	processing_objects.Remove(src)
 	return ..()
 
-/obj/item/weapon/stock_parts/cell/on_varedit(modified_var)
-	if(modified_var == "self_recharge")
-		if(self_recharge)
-			processing_objects.Add(src)
-		else
-			processing_objects.Remove(src)
-	..()
+/obj/item/weapon/stock_parts/cell/vv_edit_var(var_name, var_value)
+	switch(var_name)
+		if("self_recharge")
+			if(var_value)
+				processing_objects.Add(src)
+			else
+				processing_objects.Remove(src)
+	. = ..()
 
 /obj/item/weapon/stock_parts/cell/suicide_act(mob/user)
 	to_chat(viewers(user), "<span class='suicide'>[user] is licking the electrodes of the [src.name]! It looks like \he's trying to commit suicide.</span>")

code/game/objects/objs.dm

@@ -310,4 +310,8 @@ a {
 			Item.fire_act() //Set them on fire, too
 
 /obj/proc/on_mob_move(dir, mob/user)
-	return
+	return
+
+/obj/vv_get_dropdown()
+	. = ..()
+	.["Delete all of type"] = "?_src_=vars;delall=[UID()]"