[add] HTML Purifier added to clean code

inc/3rdparty/htmlpurifier/HTMLPurifier/AttrDef/URI/Email.php

@@ -0,0 +1,20 @@
+<?php
+
+abstract class HTMLPurifier_AttrDef_URI_Email extends HTMLPurifier_AttrDef
+{
+
+    /**
+     * Unpacks a mailbox into its display-name and address
+     * @param string $string
+     * @return mixed
+     */
+    public function unpack($string)
+    {
+        // needs to be implemented
+    }
+
+}
+
+// sub-implementations
+
+// vim: et sw=4 sts=4