Make grass buildable_to

mods/default/init.lua

@@ -1004,6 +1004,7 @@ minetest.register_node("default:junglegrass", {
 	wield_image = "default_junglegrass.png",
 	paramtype = "light",
 	walkable = false,
+	buildable_to = true,
 	groups = {snappy=3,flammable=2,attached_node=1},
 	sounds = default.node_sound_leaves_defaults(),
 	selection_box = {
@@ -1841,6 +1842,7 @@ minetest.register_node("default:grass_1", {
 	wield_image = "default_grass_3.png",
 	paramtype = "light",
 	walkable = false,
+	buildable_to = true,
 	groups = {snappy=3,flammable=3,attached_node=1},
 	sounds = default.node_sound_leaves_defaults(),
 	selection_box = {
@@ -1863,6 +1865,7 @@ minetest.register_node("default:grass_2", {
 	wield_image = "default_grass_2.png",
 	paramtype = "light",
 	walkable = false,
+	buildable_to = true,
 	drop = "default:grass_1",
 	groups = {snappy=3,flammable=3,attached_node=1,not_in_creative_inventory=1},
 	sounds = default.node_sound_leaves_defaults(),
@@ -1879,6 +1882,7 @@ minetest.register_node("default:grass_3", {
 	wield_image = "default_grass_3.png",
 	paramtype = "light",
 	walkable = false,
+	buildable_to = true,
 	drop = "default:grass_1",
 	groups = {snappy=3,flammable=3,attached_node=1,not_in_creative_inventory=1},
 	sounds = default.node_sound_leaves_defaults(),
@@ -1896,6 +1900,7 @@ minetest.register_node("default:grass_4", {
 	wield_image = "default_grass_4.png",
 	paramtype = "light",
 	walkable = false,
+	buildable_to = true,
 	drop = "default:grass_1",
 	groups = {snappy=3,flammable=3,attached_node=1,not_in_creative_inventory=1},
 	sounds = default.node_sound_leaves_defaults(),
@@ -1913,6 +1918,7 @@ minetest.register_node("default:grass_5", {
 	wield_image = "default_grass_5.png",
 	paramtype = "light",
 	walkable = false,
+	buildable_to = true,
 	drop = "default:grass_1",
 	groups = {snappy=3,flammable=3,attached_node=1,not_in_creative_inventory=1},
 	sounds = default.node_sound_leaves_defaults(),