April sync (#360)

* Maps and things no code/icons

* helpers defines globalvars

* Onclick world.dm orphaned_procs

* subsystems

Round vote and shuttle autocall done here too

* datums

* Game folder

* Admin - chatter modules

* clothing - mining

* modular computers - zambies

* client

* mob level 1

* mob stage 2 + simple_animal

* silicons n brains

* mob stage 3 + Alien/Monkey

* human mobs

* icons updated

* some sounds

* emitter y u no commit

* update tgstation.dme

* compile fixes

* travis fixes

Also removes Fast digest mode, because reasons.

* tweaks for travis Mentors are broke again

Also fixes Sizeray guns

* oxygen loss fix for vore code.

* removes unused code

* some code updates

* bulk fixes

* further fixes

* outside things

* whoops.

* Maint bar ported

* GLOBs.

code/controllers/subsystem/processing/overlays.dm

@@ -1,6 +1,4 @@
-var/datum/controller/subsystem/processing/overlays/SSoverlays
-
-/datum/controller/subsystem/processing/overlays
+PROCESSING_SUBSYSTEM_DEF(overlays)
 	name = "Overlay"
 	flags = SS_TICKER|SS_FIRE_IN_LOBBY
 	wait = 1
@@ -13,8 +11,7 @@ var/datum/controller/subsystem/processing/overlays/SSoverlays
 	var/list/overlay_icon_cache
 	var/initialized = FALSE
 
-/datum/controller/subsystem/processing/overlays/New()
-	NEW_SS_GLOBAL(SSoverlays)
+/datum/controller/subsystem/processing/overlays/PreInit()
 	LAZYINITLIST(overlay_icon_state_caches)
 	LAZYINITLIST(overlay_icon_cache)
 
@@ -171,7 +168,7 @@ var/datum/controller/subsystem/processing/overlays/SSoverlays
 	
 	var/list/cached_other = other.our_overlays
 	if(cached_other)
-		if(cut_old)
+		if(cut_old || !LAZYLEN(our_overlays))
 			our_overlays = cached_other.Copy()
 		else
 			our_overlays |= cached_other