Added a config option which forbids the possessing of singularities. This option defaults to allowing the possession of singularities.

git-svn-id: http://tgstation13.googlecode.com/svn/trunk@2697 316c924e-a436-60f5-8080-3fe189b3f50e

code/game/vials.dm

@@ -271,6 +271,12 @@
 /proc/possess(obj/O as obj in world)
 	set name = "Possess Obj"
 	set category = "Object"
+
+	if(istype(O,/obj/machinery/singularity))
+		if(config.forbid_singulo_possession)
+			usr << "It is forbidden to possess singularities."
+			return
+
 	usr.loc = O
 	usr.real_name = O.name
 	usr.name = O.name