strip_tags_long: use htmlpurifier to properly reformat html content

lib/htmlpurifier/library/HTMLPurifier/HTMLModule/Tidy/XHTML.php

@@ -0,0 +1,17 @@
+<?php
+
+class HTMLPurifier_HTMLModule_Tidy_XHTML extends HTMLPurifier_HTMLModule_Tidy
+{
+
+    public $name = 'Tidy_XHTML';
+    public $defaultLevel = 'medium';
+
+    public function makeFixes() {
+        $r = array();
+        $r['@lang'] = new HTMLPurifier_AttrTransform_Lang();
+        return $r;
+    }
+
+}
+
+// vim: et sw=4 sts=4