Add datastorage, fix player_monoids support, tweak wind

lib/datastorage.lua

@@ -0,0 +1,48 @@
+local default_state = {
+	heat = 1,
+	humidity = 1,
+	wind = vector.new(0, 0, -0.25),
+	current_weather = "auto",
+	time = {
+		last_check = 0,
+		day = 1
+	}
+}
+
+local function use_datastorage()
+	local state = datastorage.get(weather_mod.modname, "weather_state")
+	for key, val in pairs(default_state) do
+		if type(state[key]) == "nil" then
+			state[key] = val
+		end
+	end
+	return state
+end
+
+local function use_filesystem()
+	local file_name = minetest.get_worldpath() .. "/" .. weather_mod.modname
+	minetest.register_on_shutdown(function()
+		local file = io.open(file_name, "w")
+		file:write(minetest.serialize(weather_mod.state))
+		file:close()
+	end)
+
+	local file = io.open(file_name, "r")
+	if file ~= nil then
+		local storage = minetest.deserialize(file:read("*a"))
+		file:close()
+		if type(storage) == "table" then
+			return storage
+		end
+	end
+	return default_state
+end
+
+function weather_mod.get_storage()
+	local mod_datastorage = minetest.get_modpath("datastorage") ~= nil
+	if mod_datastorage then
+		return use_datastorage()
+	else
+		return use_filesystem()
+	end
+end