Upgrading Font Awesome vendor files from 3.2.1 to 4.2.0

* updating vendor files
* updating class syntax (to new FA-based classes) for all UI elements
* correcting broken tests

cms/templates/export_git.html

@@ -39,7 +39,7 @@
         <ul class="list-actions">
           <li class="item-action">
             <a class="action action-export-git"" action-primary" href="${reverse('export_git', kwargs=dict(course_key_string=unicode(context_course.id)))}?action=push">
-              <i class="icon-download"></i>
+              <i class="icon fa fa-arrow-circle-o-down"></i>
               <span class="copy">${_("Export to Git")}</span>
             </a>
           </li>