instruction blocks: remove background, use default_stone_brick.png as background texture

nodes.lua

@@ -47,8 +47,9 @@ minetest.register_node("illuna:welcome_block_3", {
 
 minetest.register_node("illuna:instruction_block_1", {
 	description = "Instruction Block 1",
-	tiles = {"instruction_block_1.png"},
+	tiles = {"default_stone_brick", "default_stone_brick", "default_stone_brick", "default_stone_brick", "default_stone_brick", "default_stone_brick^instruction_block_1.png"},
 	groups = {unbreakable = 1},
+    on_place = minetest.rotate_node,
 	    sounds = default.node_sound_dirt_defaults({
         footstep = {name="default_gravel_footstep", gain=0.5},
         dug = {name="default_gravel_footstep", gain=1.0},
@@ -63,8 +64,10 @@ minetest.register_node("illuna:instruction_block_1", {
 
 minetest.register_node("illuna:instruction_block_2", {
 	description = "Instruction Block 2",
-	tiles = {"instruction_block_2.png"},
+	tiles = {"default_stone_brick", "default_stone_brick", "default_stone_brick", "default_stone_brick", "default_stone_brick", "default_stone_brick^instruction_block_2.png"},
+    paramtype2 = "facedir",
 	groups = {unbreakable = 1},
+    on_place = minetest.rotate_node,
 	    sounds = default.node_sound_dirt_defaults({
         footstep = {name="default_gravel_footstep", gain=0.5},
         dug = {name="default_gravel_footstep", gain=1.0},
@@ -79,8 +82,10 @@ minetest.register_node("illuna:instruction_block_2", {
 
 minetest.register_node("illuna:instruction_block_3", {
 	description = "Instruction Block 3",
-	tiles = {"instruction_block_3.png"},
+	tiles = {"default_stone_brick", "default_stone_brick", "default_stone_brick", "default_stone_brick", "default_stone_brick", "default_stone_brick^instruction_block_3.png"},
+    paramtype2 = "facedir",
 	groups = {unbreakable = 1},
+    on_place = minetest.rotate_node,
 	    sounds = default.node_sound_dirt_defaults({
         footstep = {name="default_gravel_footstep", gain=0.5},
         dug = {name="default_gravel_footstep", gain=1.0},
@@ -95,8 +100,10 @@ minetest.register_node("illuna:instruction_block_3", {
 
 minetest.register_node("illuna:instruction_block_4", {
 	description = "Instruction Block 4",
-	tiles = {"instruction_block_4.png"},
+	tiles = {"default_stone_brick", "default_stone_brick", "default_stone_brick", "default_stone_brick", "default_stone_brick", "default_stone_brick^instruction_block_4.png"},
+    paramtype2 = "facedir",
 	groups = {unbreakable = 1},
+    on_place = minetest.rotate_node,
 	    sounds = default.node_sound_dirt_defaults({
         footstep = {name="default_gravel_footstep", gain=0.5},
         dug = {name="default_gravel_footstep", gain=1.0},