Remove .html extension from links

chrome/common/extensions/docs/templates/intros/pageCapture.html

 <p>
 MHTML is a <a href="http://tools.ietf.org/html/rfc2557">standard format</a>
 supported by most browsers. It encapsulates in a single file a page and all
 its resources (CSS files, images..).
 </p>
 
 <p>
 Note that for security reasons a MHTML file can only be loaded from the file
 system and that it can only be loaded in the main frame.
 </p>
 
 <h2 id="manifest">Manifest</h2>
 
 
 <p>You must declare the "pageCapture" permission
-in the <a href="manifest.html">extension manifest</a>
+in the <a href="manifest">extension manifest</a>
 to use the pageCapture API.
 For example:</p>
 <pre data-filename="manifest.json">
 {
   "name": "My extension",
   ...
   <b>"permissions": [
     "pageCapture"
   ]</b>,
   ...
 }
 </pre>