add smarty lib

libs/plugins/variablefilter.htmlspecialchars.php

@@ -0,0 +1,19 @@
+<?php
+/**
+ * Smarty plugin
+ *
+ * @package    Smarty
+ * @subpackage PluginsFilter
+ */
+
+/**
+ * Smarty htmlspecialchars variablefilter plugin
+ *
+ * @param string $source input string
+ *
+ * @return string filtered output
+ */
+function smarty_variablefilter_htmlspecialchars($source)
+{
+    return htmlspecialchars($source, ENT_QUOTES, Smarty::$_CHARSET);
+}