Remove thin air and vacuum

It simply does not fit to the mod’s goals.

init.lua

@@ -167,52 +167,6 @@ function pedology.sun_dry(pos, node, active_object_count, active_object_wider)
 end
 
 
-
---[[ air and vacuum]]
-minetest.register_node("pedology:vacuum", {
-	description = "vacuum",
-	inventory_image="unknown_node.png",
-	wield_image="unknown_node.png",
-	paramtype="light",
-	drawtype="airlike",
-	damage_per_second=8,
-	drowning=8,
-	sunlight_propagates=true,
-	walkable=false,
-	pointable=false,
-	diggable=false,
-	buildable_to=true,
-	groups={not_in_creative_inventory=1}
-})
-
-minetest.register_node("pedology:thinair2", {
-	description = "very thin air",
-	inventory_image="unknown_node.png",
-	wield_image="unknown_node.png",
-	paramtype="light",
-	drawtype="airlike",
-	sunlight_propagates=true,
-	walkable=false,
-	pointable=false,
-	diggable=false,
-	buildable_to=true,
-	groups={not_in_creative_inventory=1}
-})
-
-minetest.register_node("pedology:thinair1", {
-	description = "thin air",
-	inventory_image="unknown_node.png",
-	wield_image="unknown_node.png",
-	paramtype="light",
-	drawtype="airlike",
-	sunlight_propagates=true,
-	walkable=false,
-	pointable=false,
-	diggable=false,
-	buildable_to=true,
-	groups={not_in_creative_inventory=1}
-})
-
 --[[ liquids ]]
 
 function pedology.register_liquid(basename, description, alpha, viscosity, drowning, damage_per_second, post_effect_color, additional_groups)