Calculate total phases and display

views/change.html.twig

@@ -2,7 +2,7 @@
 
 {% block content %}
     <header class="page-header">
-        <h1>Change blindness test (step {{ step_count }} of 3)</h1>
+        <h1>Change blindness test (step {{ step_count }} of {{ step_total }})</h1>
     </header>
     <div id="placeholder" class="well">
         <p>Please wait while the images are loaded.</p>