Introduce Program to include cfp/rooms/tracks/events/event_types/difficulty_levels

app/views/conference/schedule.html.erb

@@ -1,5 +1,5 @@
 <div class="container">
-  <% if @conference.events.scheduled.any? %>
+  <% if @conference.program.events.scheduled.any? %>
       <div role="tabpanel">
         <!-- Nav tabs -->
         <ul class="nav nav-tabs" role="tablist">
@@ -24,4 +24,4 @@
   <% else %>
       <%= render 'all_events' %>
   <% end %>
-</div>
+</div>