title: Day Button and Week Button is not displayed
body: <p>I am using fullcalendar with angularjs to display events. Currently the month view is working correctly. But <strong>day button</strong> and <strong>week button</strong> aren't displayed in the UI.In both Left and right side Only Today, back and next buttons are displayed.I can't figure out the reason for that. Please find the below code.</p>
  
  <p>view.html</p>
  
  <pre><code>&lt;html&gt;
  &lt;head&gt;
  &lt;link rel="stylesheet" href="../fullcalendar-4.1.0/packages/core/main.css"&gt;&lt;/script&gt;
  &lt;link rel="stylesheet" href="../fullcalendar-4.1.0/packages/daygrid/main.css"&gt;&lt;/script&gt;
  &lt;link rel="stylesheet" href="../fullcalendar-4.1.0/packages/list/main.css"&gt;&lt;/script&gt;
  &lt;link rel="stylesheet" href="../fullcalendar-4.1.0/packages/timegrid/main.css"&gt;&lt;/script&gt;
  &lt;script type="text/javascript" src="../fullcalendar-4.1.0/packages/core/main.js"&gt;&lt;/script&gt;
      &lt;script type="text/javascript" src="../fullcalendar-4.1.0/packages/daygrid/main.js"&gt;&lt;/script&gt;
      &lt;script type="text/javascript" src="../fullcalendar-4.1.0/packages/timegrid/main.js"&gt;&lt;/script&gt;
      &lt;script type="text/javascript" src="../fullcalendar-4.1.0/packages/list/main.js"&gt;&lt;/script&gt;
  &lt;/head&gt;
  &lt;script&gt;
  $scope.event = {events: [{
              title:'test1',
              start: '2019-05-05 08:00',
              end: '2019-05-10 08:00'
            },
            {
              title:'test2',
              start: '2019-05-05 12:00'
          }]};
      var calendarEl = document.getElementById('calendar');
  
          var calendar = new FullCalendar.Calendar(calendarEl, {
              events: $scope.event.events,
              plugins: [ 'dayGrid','timeGrid','list' ],
              header: {
      left: 'prev,next today',
      center: 'title',
      right: 'month,agendaWeek,agendaDay'
  }
          });
          calendar.render();
      });
  &lt;/script&gt;
  &lt;body ng-app="myApp" ng-controller="myController"&gt;
     &lt;div id="calendar" ng-model="eventSources"&gt;&lt;/div&gt;    
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>