title: How to display all dates with a given Start Date and End Date even if there is no data?
body: <p>I'm totally new to Highcharts Gantt and as the title says; How to display all dates with a given Start Date and End Date even if there is no data?</p>
  
  <p><a href="https://i.stack.imgur.com/2E6Aa.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/2E6Aa.jpg" alt="Doesn&#39;t show all other dates"></a></p>
  
  <p>I'm using the following code:</p>
  
  <pre><code>Highcharts.ganttChart(id, {
              chart: {
                  panning: true,
                  style: {
                      fontFamily: 'Lato'
                  }
              },
              tooltip: {
                  pointFormat: '&lt;span&gt;{point.customerLastName}&lt;/span&gt;&lt;br&gt;&lt;span&gt;From: {point.start:%e. %b . %Y}&lt;/span&gt;&lt;br/&gt;&lt;span&gt;To: {point.end:%e. %b. %Y}&lt;/span&gt;',
                  followTouchMove: true
              },
              xAxis: [{
                      // first x-axis
                      tickInterval: month,
                      showEmpty: true,
                  },
                  {
                      // second x-axis
                      tickInterval: day,
                      showEmpty: true,
                  }
  
              ],
              yAxis: {
                  plotBands: {
                      thickness: 120
                  },
                  categories: data.labels,
                  showEmpty: true,
                  min: 0,
                  max: data.labels.length
              },
              allowPointSelect: true,
              plotOptions: {
                  series: {
                      animation: true,
                      dragDrop: {
                          draggableX: true,
                          draggableY: true,
                          dragPrecisionX: day
                      },
                      dataLabels: {
                          enabled: true,
                          format: '{point.customerLastName}',
                          style: {
                              cursor: 'default',
                              pointerEvents: 'none'
                          }
                      },
                      allowPointSelect: true,
                      events: {
                          click: function(a) {
                              var data = JSON.parse(a.point.jsonData);
                              data.referrer = "occupation-plan";
                              console.log(data);
                              $(document).trigger('booking-modal-edit', JSON.stringify(data));
                          }
                      }
                  },
              },
              series: data.series,
          });
  </code></pre>
  
  <p>The series data is fine, however I really wanted to display all the dates in a given start date and end date even if there is no data for those dates in the series.</p>