added update script for v2.4.1

setup/update_scripts/update-drom-2.4-to-2.4.1.php

@@ -0,0 +1,14 @@
+<?php
+/**
+ * @Author: printempw
+ * @Date:   2016-04-04 08:47:35
+ * @Last Modified by:   printempw
+ * @Last Modified time: 2016-04-04 08:48:06
+ */
+
+if (!defined('BASE_DIR')) exit('请运行 /setup/update.php 来升级');
+
+if (Option::get('current_version') == "2.4") {
+    Option::set('current_version', '2.4.1');
+    echo "已成功升级至 v2.4.1";
+}