Add image to UML index page q

Author: stopsopa

pages/uml/index.html

@@ -36,6 +36,7 @@ <h2>Sequence diagram</h2>
               (where request can go right or left with no issues - the same response)
 
           </script>
+          <img src="https://i.imgur.com/e0osy21.png" />
         </fieldset>
       </div>
     </div>