[feat]Add valid date range to fullcalendar

app/assets/javascripts/fullcalendar.js

@@ -10,6 +10,10 @@ $( document ).ready(function() {
       allDaySlot: false,
       slotMinTime: fullcalData.data('startHour') + ':00:00',
       slotMaxTime: fullcalData.data('endHour') + ':00:00',
+      validRange: {
+        start: fullcalData.data('startDate'),
+        end: fullcalData.data('endDate')
+      },
       timeZone: 'UTC', // TODO: Events are stored in conference's timezone implicitly (UTC+0) in the database 
       initialDate: fullcalData.data('day'),
       initialView: 'resourceTimeGridDay',

app/views/schedules/vertical_schedule.haml

@@ -8,4 +8,6 @@
   #vert-schedule-full-calendar
   #fullcalendar{ data: { rooms: @rooms, events: @event_schedules, day: @day,
   'start-hour': @conference.start_hour, 'end-hour': @conference.end_hour,
+  'start-date': @conference.start_date,
+  'end-date': @conference.end_date + 1.day,
   'scheduler-license-key': @scheduler_license_key } }