title: highcharts: disable default buttons but keep custom button
body: <p>In this fiddle <a href="http://jsfiddle.net/2d2hrnzw/" rel="nofollow">here</a>, I've tried to disable the default highcharts button while keeping the custom button, but I'm unable to actually do so. To disable the default buttons but keep the custom button, I tried this:</p>
  
  <pre><code>exporting: {
              buttons: {
                  printButton: {
                      enabled: false
                  },
                  exportButton: {
                      enabled: false
                  },
                  customButton: {
                      x: -62,
                      onclick: function () {
                          alert('Clicked');
                      },
                      symbol: 'circle'
                  }
              }
          }
  </code></pre>
  
  <p>All the other SO questions I've seen, like <a href="https://stackoverflow.com/questions/10375871/highchart-hide-default-buttons">this</a> one, have suggested this method for disabling the default buttons, and I'm not quite sure why this isn't working. Any help? </p>