Mob refactoring.

Updates Bump() code.
Intents now use constants.
Simple animals can now use languages without overriding say().
There is now a difference between being able to smash normal and reinforced walls.
Reworks simple_animal/attackby so that constructs don't need to override it simply to add damage resistance.

code/game/objects/structures/stool_bed_chair_nest/wheelchair.dm

@@ -137,10 +137,10 @@
 	..()
 	if(!buckled_mob)	return
 
-	if(propelled || (pulling && (pulling.a_intent == "hurt")))
+	if(propelled || (pulling && (pulling.a_intent == I_HURT)))
 		var/mob/living/occupant = unbuckle_mob()
 
-		if (pulling && (pulling.a_intent == "hurt"))
+		if (pulling && (pulling.a_intent == I_HURT))
 			occupant.throw_at(A, 3, 3, pulling)
 		else if (propelled)
 			occupant.throw_at(A, 3, propelled)

code/game/objects/structures/tables_racks.dm

@@ -363,7 +363,7 @@
 		if (istype(G.affecting, /mob/living))
 			var/mob/living/M = G.affecting
 			if (G.state < 2)
-				if(user.a_intent == "hurt")
+				if(user.a_intent == I_HURT)
 					if (prob(15))	M.Weaken(5)
 					M.apply_damage(8,def_zone = "head")
 					visible_message("<span class='danger'>[G.assailant] slams [G.affecting]'s face against \the [src]!</span>")

code/game/objects/structures/window.dm

@@ -180,7 +180,7 @@
 		user.visible_message("<span class='danger'>[user] smashes through [src]!</span>")
 		shatter()
 
-	else if (usr.a_intent == "hurt")
+	else if (usr.a_intent == I_HURT)
 
 		if (istype(usr,/mob/living/carbon/human))
 			var/mob/living/carbon/human/H = usr