Thrown items can be targeted, has miss chance...

...based on distance, similar to projectiles.

code/modules/reagents/grenade_launcher.dm

@@ -56,7 +56,7 @@
 			var/obj/item/weapon/grenade/chem_grenade/F = grenades[1] //Now with less copypasta!
 			grenades -= F
 			F.loc = user.loc
-			F.throw_at(target, 30, 2)
+			F.throw_at(target, 30, 2, user)
 			message_admins("[key_name_admin(user)] fired a grenade ([F.name]) from a grenade launcher ([src.name]).")
 			log_game("[key_name_admin(user)] used a grenade ([src.name]).")
 			F.active = 1