docs: fix header link to removed website, point to new location

Author: clintonsteiner

doc/_themes/saltstack2/layout.html

@@ -166,11 +166,11 @@
                 <li><a href="/en/latest/">Overview</a></li>
                 <li><a href="https://docs.saltproject.io/salt/user-guide/en/latest/">Salt User Guide</a></li>
                 <li><a href="/en/latest/contents.html">Documentation</a></li>
-                <li><a href="https://repo.saltproject.io">Downloads</a></li>
+                <li><a href="https://packages.broadcom.com/artifactory/saltproject-rpm/">Downloads</a></li>
                 <li><a href="/en/latest/topics/development/">Develop</a></li>
                             <!--<li><a href="/en/2016.3/faq/">FAQ</a></li>
                             <li><a href="/en/2016.3/samples/">Code Samples</a></li>-->
-                            <!--                <li><a href="https://repo.saltproject.io" target="_blank">Downloads</a></li>-->
+                            <!--                <li><a href="https://packages.broadcom.com/artifactory/saltproject-rpm/" target="_blank">Downloads</a></li>-->
                             <!--<li><a href="http://saltstack.com/training" target="_blank">Training</a></li>
                             <li><a href="http://saltstack.com/support" target="_blank">Support</a></li>-->
                         </ul>