Added the course image to the about page, even if the video doesn't exist.

lms/templates/portal/course_about.html

@@ -37,6 +37,12 @@
           <div class="play-intro"></div>
         </div>
       </a>
+      %else:
+      <div class="media">
+        <div class="hero">
+          <img src="${course_image_url(course)}" />
+        </div>
+      </a>
       % endif
     </div>
   </header>