Remove .html extension from links

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

 <img src="{{static}}/images/bookmarks.png"
      width="486" height="211" alt="Clicking the star adds a bookmark" />
 
 <h2 id="manifest">Manifest</h2>
 <p>You must declare the "bookmarks" permission
-in the <a href="manifest.html">extension manifest</a>
+in the <a href="manifest">extension manifest</a>
 to use the bookmarks API.
 For example:</p>
 <pre data-filename="manifest.json">
 {
   "name": "My extension",
   ...
   <b>"permissions": [
     "bookmarks"
   ]</b>,
   ...
@@ skipping 56 matching lines @@
 <pre>
 chrome.bookmarks.create({'parentId': extensionsFolderId,
                          'title': 'Extensions doc',
                          'url': 'http://code.google.com/chrome/extensions'});
 </pre>
 
 <p>
 For an example of using this API, see the
 <a href="http://src.chromium.org/viewvc/chrome/trunk/src/chrome/common/extensions/docs/examples/api/bookmarks/basic/">basic bookmarks sample</a>.
 For other examples and for help in viewing the source code, see
-<a href="samples.html">Samples</a>.
+<a href="samples">Samples</a>.
 </p>