Remove .html extension from links

chrome/common/extensions/docs/templates/articles/desktop_notifications.html

 <h1>Rich Notifications</h1>
 
 <p class="warning"><b>Warning:</b>
 <code>webKitNotifications.createHTMLNotification()</code> in the
 <a href="http://www.chromium.org/developers/design-documents/desktop-notifications/api-specification">web notifications API</a> has been deprecated.
 The new <a href="http://www.w3.org/TR/notifications/">web notifications API</a> only allows text.
-<a href="notifications.html">Chrome notifications API</a>
+<a href="notifications">Chrome notifications API</a>
 will be promoted to stable soon and
 web notifications will be updated
 to use the new rich notifications format.
 </p>
 
 <p>
 Use rich desktop notifications to notify users that something
 important has happened.
 Notifications appear outside the browser window.
 As the following snapshots show,
@@ skipping 87 matching lines @@
 
 <h2 id="examples">More Examples</h2>
 
 <p>
 You can find a simple example
 of using notifications in the
 <a href="http://src.chromium.org/viewvc/chrome/trunk/src/chrome/common/extensions/docs/examples/api/notifications/">examples/api/notifications</a>
 directory.
 For other examples
 and for help in viewing the source code,
-see <a href="samples.html">Samples</a>.
+see <a href="samples">Samples</a>.
 </p>
 
 <p>
 Also see html5rocks.com's
 <a href="http://www.html5rocks.com/tutorials/notifications/quick/">notifications tutorial</a>.
 Ignore the permission-related code;
 it's unnecessary if you declare the "notifications" permission.
 </p>