Add Types TOC entry for XMLDocument.

Author: dmethvin

pages/Types.html

@@ -91,6 +91,7 @@
   <li class="toclevel-1"><a href="#Deferred"><span class="toctext">Deferred Object</span></a></li>
   <li class="toclevel-1"><a href="#Promise"><span class="toctext">Promise Object</span></a></li>
   <li class="toclevel-1"><a href="#Callbacks"><span class="toctext">Callbacks Object</span></a></li>
+  <li class="toclevel-1"><a href="#XMLDocument"><span class="toctext">XML Document</span></a></li>
 </ol>
 
 <h2 id="String"> String </h2>