Add website to client repository

Closes #1567

The main reason I'm not simply merging Annika's PR is because this
way makes it clearer that I'm taking responsibility for all this
code, that it's mostly code I wrote, and also because it makes it
easier to ensure that none of the files have been changed.

(Not that I don't personally trust Annika, but I have something
resembling an obligation to users not to expose them to risks based
on personal trust.)

website/lib/htmlpurifier/HTMLPurifier/HTMLModule/Proprietary.php

@@ -0,0 +1,33 @@
+<?php
+
+/**
+ * Module defines proprietary tags and attributes in HTML.
+ * @warning If this module is enabled, standards-compliance is off!
+ */
+class HTMLPurifier_HTMLModule_Proprietary extends HTMLPurifier_HTMLModule
+{
+
+    public $name = 'Proprietary';
+
+    public function setup($config) {
+
+        $this->addElement('marquee', 'Inline', 'Flow', 'Common',
+            array(
+                'direction' => 'Enum#left,right,up,down',
+                'behavior' => 'Enum#alternate',
+                'width' => 'Length',
+                'height' => 'Length',
+                'scrolldelay' => 'Number',
+                'scrollamount' => 'Number',
+                'loop' => 'Number',
+                'bgcolor' => 'Color',
+                'hspace' => 'Pixels',
+                'vspace' => 'Pixels',
+            )
+        );
+
+    }
+
+}
+
+// vim: et sw=4 sts=4