Blood_DNA fixes.

Bloodied icons rewritten to be overlays, not replacing the icons. Hopefully this should fix \icon[src] breaking everything.
Bloodied hands/gloves don't transfer blood to infinite amounts of touched items.

Please report any bugs!

git-svn-id: http://tgstation13.googlecode.com/svn/trunk@3290 316c924e-a436-60f5-8080-3fe189b3f50e

code/defines/obj.dm

@@ -270,7 +270,7 @@
 /obj/item
 	name = "item"
 	icon = 'items.dmi'
-	var/icon_old = null//For when weapons get bloodied this saves their old icon.
+	var/icon/blood_overlay = null //this saves our blood splatter overlay, which will be processed not to go over the edges of the sprite
 	var/abstract = 0
 	var/force = 0
 	var/item_state = null