minetest.create_detached_inventory(name, callbacks) -> InvRef
^ callbacks: See "Detached inventory callbacks"
^ Creates a detached inventory. If it already exists, it is cleared.
+minetest.show_formspec(playername, formspec)
+^ playername: name of player to show formspec
+^ formspec: formspec to display
Item handling:
minetest.inventorycube(img1, img2, img3)