Removing link to test-cors.org

CORS is fairly mature at this point and the test site is fairly unused.

_layouts/default.html

@@ -40,7 +40,6 @@
 						<li><a href="server.html" title="I want to add CORS support to my server">Server</a></li>
 						<li><a href="client.html" title="I want to use CORS from JavaScript">Client</a></li>
 						<li><a href="resources.html" title="More resources">Resources</a></li>
-						<li><a href="https://www.test-cors.org" title="I want to test CORS capabilities" target="_blank">Test</a></li>
 						<li class="divider-vertical"></li>
 						<li><a href="https://github.com/mhausenblas/enable-cors.org/issues" target="_blank"><i class="icon-share-alt icon-white"></i> Suggest!</a></li>
 						<li><a href="https://stackoverflow.com/questions/tagged/cors" target="_blank"><i class="icon-share-alt icon-white"></i> Help!</a></li>