[Website] Add link to top-level documentation to nav dropdown

Change-Id: Ie885cbdf9309eaddb639aa9ecf4d2d85b8fb7de8
diff --git a/_includes/header.html b/_includes/header.html
index 5344501..2abf60f 100644
--- a/_includes/header.html
+++ b/_includes/header.html
@@ -54,8 +54,9 @@
              Documentation
           </a>
           <div class="dropdown-menu" aria-labelledby="navbarDropdownDocumentation">
+            <a class="dropdown-item" href="{{ site.baseurl }}/docs">Project Docs</a>
             <a class="dropdown-item" href="{{ site.baseurl }}/docs/python">Python</a>
-            <a class="dropdown-item" href="{{ site.baseurl }}/docs/cpp">C++ API</a>
+            <a class="dropdown-item" href="{{ site.baseurl }}/docs/cpp">C++</a>
             <a class="dropdown-item" href="{{ site.baseurl }}/docs/java">Java API</a>
             <a class="dropdown-item" href="{{ site.baseurl }}/docs/c_glib">C GLib API</a>
             <a class="dropdown-item" href="{{ site.baseurl }}/docs/js">Javascript API</a>