Replace deprecated methods:

- 'setting_get' with 'settings:get'
- 'setting_getbool' with 'settings:get_bool'

mesecons/settings.lua

 -- SETTINGS
 function mesecon.setting(setting, default)
 	if type(default) == "boolean" then
-		local read = minetest.setting_getbool("mesecon."..setting)
+		local read = minetest.settings:get_bool("mesecon."..setting)
 		if read == nil then
 			return default
 		else
 			return read
 		end
 	elseif type(default) == "string" then
-		return minetest.setting_get("mesecon."..setting) or default
+		return minetest.settings:get("mesecon."..setting) or default
 	elseif type(default) == "number" then
-		return tonumber(minetest.setting_get("mesecon."..setting) or default)
+		return tonumber(minetest.settings:get("mesecon."..setting) or default)
 	end
 end