Small cleanups in internal.lua, move forceloading reversal to legacy

mesecons/legacy.lua

@@ -28,3 +28,10 @@ function mesecon.receptor_off(self, pos, rules)
 	mesecon.queue:add_action(pos, "receptor_off", {rules}, nil, rules)
 end
 
+-- Un-forceload any forceloaded mapblocks from older versions of Mesecons which
+-- used forceloading instead of VoxelManipulators.
+local old_forceloaded_blocks = mesecon.file2table("mesecon_forceloaded")
+for hash, _ in pairs(old_forceloaded_blocks) do
+	minetest.forceload_free_block(unhash_blockpos(hash))
+end
+os.remove(minetest.get_worldpath()..DIR_DELIM.."mesecon_forceloaded")