Add in system to exclude specific reagents from cooked items

- You can now add explicit "forbidden reagents" in cooked recipes, if
for instance, your ingredients have toxins and your cooked food "refines
that". In that case, simply add "toxin" to the exception list
- Base code added to recipe.dm, example adder under
/datum/recipe/aesirsalad

code/datums/recipe.dm

@@ -40,6 +40,7 @@
 /datum/recipe
 
 	var/list/reagents //List of reagents needed and their amount, reagents = list("berryjuice" = 5)
+	var/list/reagents_forbidden //List of reagents that will not be transfered to the cooked item under any circumstance, use smartly and sparringly. reagents_forbidden = list("toxin", "water")
 	var/list/items //List of items needed, items = list(/obj/item/weapon/crowbar, /obj/item/weapon/welder)
 	var/result //Well gee, what we output, result = /obj/item/weapon/reagent_containers/food/snacks/donut/normal
 	var/time = 100 //In tenths of a second, this is how long it takes for the magic to happen. The machine producing the recipe handles this value, but the recipe defines it
@@ -97,6 +98,9 @@
 	var/obj/result_obj = new result(container) //Spawn the result of our little cuisine in the recipe machine in advance to transfer reagents
 	for(var/obj/O in (container.contents - result_obj)) //Find all objects (for instance, raw food or beakers) in our machine, excluding the result we just created
 		if(O.reagents) //Little sanity, can't hurt
+			for(var/r_r in reagents_forbidden) //Check forbidden reagents
+				O.reagents.del_reagent("[r_r]") //If we find any, remove
+			O.reagents.update_total() //Make sure we're set
 			O.reagents.trans_to(result_obj, O.reagents.total_volume) //If we have reagents in here, squeeze them into the end product
 		qdel(O) //Delete the object, he has outlived his usefulness
 	container.reagents.clear_reagents() //Clear all the reagents we haven't transfered, for instance if we need to cook in water

code/modules/food/recipes_microwave.dm

@@ -1109,6 +1109,7 @@
 		/obj/item/weapon/reagent_containers/food/snacks/grown/goldapple,
 		)
 	result = /obj/item/weapon/reagent_containers/food/snacks/aesirsalad
+	reagents_forbidden = list("synaptizine")
 
 /datum/recipe/validsalad
 	items = list(