Revert "remove htmlpurifier"

This reverts commit c21a462d52.

lib/htmlpurifier/library/HTMLPurifier/Token/End.php

@@ -0,0 +1,19 @@
+<?php
+
+/**
+ * Concrete end token class.
+ *
+ * @warning This class accepts attributes even though end tags cannot. This
+ * is for optimization reasons, as under normal circumstances, the Lexers
+ * do not pass attributes.
+ */
+class HTMLPurifier_Token_End extends HTMLPurifier_Token_Tag
+{
+    /**
+     * Token that started this node. Added by MakeWellFormed. Please
+     * do not edit this!
+     */
+    public $start;
+}
+
+// vim: et sw=4 sts=4