Persistence Patch

- Fixes Paper and font tags stacking across rounds, as shown in: ![](https://cdn.discordapp.com/attachments/187013248309002240/741937939382141000/164fdd3a37fb22f18dfa9b5c431ffc04.png)

- Fixes Persistence being always-on because of if("persistence_enabled") config.persistence_enabled = 1. As explained: 
> it's on by default, which means config.txt will be read and if it's not there it stays at 1. If it is there,it gets set to 1. There is no way to disable it

- Adds config options to enable/disable **Persistence for Maploaded objects**, as well as a verb to toggle such.
- Adds Persistence to config.

Currently IGNORE_MAPLOAD for Persistance is **Disabled.**
Maploaded objects/dirt/etc will be saved by persistence, preserving current behavior.

You will need to update config.txt with the following lines:
\## Uncomment this to DISABLE persistence 
\#PERSISTENCE_DISABLED 
 
\## Uncomment this to DISABLE maploaded trash/paper/etc from being saved by the persistence system. 
\#PERSISTENCE_IGNORE_MAPLOAD

code/game/objects/effects/decals/cleanable.dm

@@ -12,12 +12,13 @@ generic_filth = TRUE means when the decal is saved, it will be switched out for
 	var/age = 0
 	var/list/random_icon_states = list()
 
-/obj/effect/decal/cleanable/Initialize(var/ml, var/_age)
+/obj/effect/decal/cleanable/Initialize(var/mapload, var/_age)
 	if(!isnull(_age))
 		age = _age
 	if(random_icon_states && length(src.random_icon_states) > 0)
 		src.icon_state = pick(src.random_icon_states)
-	SSpersistence.track_value(src, /datum/persistent/filth)
+	if(!mapload || !config.persistence_ignore_mapload)
+		SSpersistence.track_value(src, /datum/persistent/filth)
 	. = ..()
 
 /obj/effect/decal/cleanable/Destroy()