Make bark nodes usable as fuel

mods/ITEMS/mcl_core/crafting.lua

@@ -526,6 +526,12 @@ minetest.register_craft({
 	burntime = 15,
 })
 
+minetest.register_craft({
+	type = "fuel",
+	recipe = "group:bark",
+	burntime = 15,
+})
+
 minetest.register_craft({
 	type = "fuel",
 	recipe = "mcl_core:ladder",

mods/ITEMS/mclx_stairs/init.lua

@@ -19,14 +19,14 @@ for b=1, #barks do
 		id = "mcl_core:"..bark[1].."tree"
 	end
 	mcl_stairs.register_stair(sub, id,
-			{handy=1,axey=1, flammable=3, material_wood=1},
+			{handy=1,axey=1, flammable=3, bark_stairs=1, material_wood=1},
 			{minetest.registered_nodes[id].tiles[3]},
 			bark[2],
 			mcl_sounds.node_sound_wood_defaults(),
 			2,
 			"woodlike")
 	mcl_stairs.register_slab(sub, id,
-			{handy=1,axey=1, flammable=3, material_wood=1},
+			{handy=1,axey=1, flammable=3, bark_slab=1, material_wood=1},
 			{minetest.registered_nodes[id].tiles[3]},
 			bark[3],
 			mcl_sounds.node_sound_wood_defaults(),
@@ -100,3 +100,16 @@ for i=1, #block.dyes do
 	end
 end
 
+-- Fuel
+minetest.register_craft({
+	type = "fuel",
+	recipe = "group:bark_stairs",
+	-- Same as wood stairs
+	burntime = 15,
+})
+minetest.register_craft({
+	type = "fuel",
+	recipe = "group:bark_slab",
+	-- Same as wood slab
+	burntime = 8,
+})