Doroob: change URL to main index for API guide

doroob.html

@@ -99,7 +99,7 @@
                 </li>
 
                 <li class="item-link">
-                  <a class="item-link__action" href="http://edx.readthedocs.io/projects/edx-platform-api/en/latest/courses/index.html">
+                  <a class="item-link__action" href="http://edx.readthedocs.io/projects/edx-platform-api/en/latest/">
                     <h4 class="item-link__title">Open edx Platform APIs</h4>
                     <div class="item-link__copy">
                       <p>Documentation for the Open edX Platform APIs, including the Courses API.</p>