Ports Stasis Cages from Baystation (#6017)

* Ports Stasis Cages from Baystation

code/modules/mob/living/simple_mob/life.dm

@@ -76,6 +76,9 @@
 /mob/living/simple_mob/proc/handle_atmos()
 	var/atmos_unsuitable = 0
 
+	if(in_stasis)
+		return 1 // return early to skip atmos checks
+
 	var/atom/A = src.loc
 
 	if(istype(A,/turf))

code/modules/mob/living/simple_mob/simple_mob.dm

@@ -151,6 +151,8 @@
 	var/purge = 0					// Cult stuff.
 	var/supernatural = FALSE		// Ditto.
 
+	// contained in a cage
+	var/in_stasis = 0
 
 /mob/living/simple_mob/Initialize()
 	verbs -= /mob/verb/observe