Some fixes to robotics surgery

Internal organ fixing surgery will now work correctly on robotic organs,
using nanopaste in place of trauma kits

Defibs also don't need the body to be past the point of deadness to work

Kitchen utensils should now properly work as surgery tools where given in
code

IPC thralls can now be dethralled by performing the surgery on where their
brain is, in this case their chest. This will also work for any species
that has a brain anywhere else in their body.

code/modules/organs/organ_external.dm

@@ -139,6 +139,9 @@
 	//robot limbs take reduced damage
 	brute_mod = 0.66
 	burn_mod = 0.66
+	// Robot parts also lack bones
+	// This is so surgery isn't kaput, let's see how this does
+	encased = null
 
 /****************************************************
 			   DAMAGE PROCS
@@ -820,6 +823,9 @@ Note that amputating the affected organ does in fact remove the infection from t
 		H.drop_item()
 	W.loc = owner
 
+/obj/item/organ/external/proc/open_enough_for_surgery()
+	return (encased ? (open == 3) : (open == 2))
+
 /obj/item/organ/external/removed(var/mob/living/user, var/ignore_children)
 
 	if(!owner)