title: angular2-highcharts first point loses on xAxis
body: <p>I have the following options:</p>
  
  <pre><code>this.options = {
        title: { text: 'simple chart' },
        series: [{
          data: [29.9, 71.5, 106.4, 129.2],
          pointInterval: 24 * 3600 * 1000,
          pointStart: Date.UTC(2015, 1, 12) // feb 12, 2015
        }],
        xAxis: {
          type: 'datetime',
          dateTimeLabelFormats: {
            minute: '%H:%M',
            hour: '%H:%M',
            day: '%e. %b',
            week: '%e. %b',
            month: '%b \'%y',
            year: '%Y'
          }
        }
      };
  </code></pre>
  
  <p>When I choose datetime and click on button:</p>
  
  <pre><code>buttonClicked() {
      let pointStart=new Date(this.dateStart);
      let year=pointStart.getFullYear();
      let month=pointStart.getMonth()+1;
      let day=pointStart.getDate();
      let hours=pointStart.getHours();
      let minutes=pointStart.getMinutes();
  
      this.chart.series[0].update({
        data: [30, 41, 47, 52],
        pointStart: Date.UTC(year, month, day, hours, minutes, 0),
        pointInterval: 24 * 3600 * 1000
      }, true);
      // this.chart.redraw()
    }
  </code></pre>
  
  <p>After redraw() first point on xAxis is lost and chart looks like this:
  <a href="https://i.stack.imgur.com/Nk6fw.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Nk6fw.png" alt="enter image description here"></a></p>
  
  <p>Any solutions?</p>