Add ODataHQ to ecosystem->tutorials

This is a pull request from ODataOrg/ecosystem
ODataOrg/ecosystem#10

Author: Qian Li

pages/ecosystem.html

@@ -473,6 +473,10 @@ <h2>Tutorials</h2>
 <td><a href="http://www.youtube.com/watch?v=jv7tP-F2mrQ">Xceed</a></td>
 <td></td>
 </tr>
+<tr>
+<td><a href="http://blog.odatahq.com/blog/2014/09/10/Connect-live-data-to-Excel/">ODataHQ</a></td>
+<td>Connect an OData service to Microsoft Excel</td>
+</tr>
 </tbody>
 </table>
 </div>