Added HTMLPurifier (http://htmlpurifier.org/) Version 3.3.0

- can be used via html class like: 

        $clean_html = html::purify($html);

- using it now in eTemplate to remove malicious code from html:
  a) when displaying "formatted text"
  b) when "formatted text" get's input by the user

phpgwapi/inc/htmlpurifier/library/HTMLPurifier/HTMLModule/StyleAttribute.php

@@ -0,0 +1,24 @@
+<?php
+
+/**
+ * XHTML 1.1 Edit Module, defines editing-related elements. Text Extension
+ * Module.
+ */
+class HTMLPurifier_HTMLModule_StyleAttribute extends HTMLPurifier_HTMLModule
+{
+
+    public $name = 'StyleAttribute';
+    public $attr_collections = array(
+        // The inclusion routine differs from the Abstract Modules but
+        // is in line with the DTD and XML Schemas.
+        'Style' => array('style' => false), // see constructor
+        'Core' => array(0 => array('Style'))
+    );
+
+    public function setup($config) {
+        $this->attr_collections['Style']['style'] = new HTMLPurifier_AttrDef_CSS();
+    }
+
+}
+
+// vim: et sw=4 sts=4