Make body bag printable in the autolathe (#2285)

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## About The Pull Request

Body bags are printable for a price of 2 plastic sheet in every
autolathe/protolathe.

## Why It's Good For The Game

Honestly they are just handy and the design feel basic enough to be
available everywere.

## Changelog

:cl:
add: Body bags in the autolathe.
/:cl:

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Co-authored-by: ritorizo <ritorizo@localhost>

code/game/objects/items/bodybag.dm

@@ -5,6 +5,7 @@
 	icon = 'icons/obj/bodybag.dmi'
 	icon_state = "bodybag_folded"
 	w_class = WEIGHT_CLASS_SMALL
+	custom_materials = list(/datum/material/plastic = 4000)
 	var/unfoldedbag_path = /obj/structure/closet/body_bag
 
 /obj/item/bodybag/attack_self(mob/user)

code/modules/research/designs/autolathe_designs.dm

@@ -1175,6 +1175,14 @@
 	build_path = /obj/item/storage/bag/trash
 	category = list("initial","Tools","Tool Designs","Misc")
 
+/datum/design/bodybag
+	name="Body Bag"
+	id="bodybag"
+	build_type = AUTOLATHE | PROTOLATHE
+	materials = list(/datum/material/plastic = 4000)
+	build_path = /obj/item/bodybag
+	category = list("initial","Medical","Misc")
+
 /datum/design/fishing_rod_basic
 	name = "Fishing Rod"
 	id = "fishing rod"