title: Highchart and yii not drawing a pie
body: <p>This code actually doesn't draw nothing but the title</p>
  
  <p>It's uses Highcharts like an yii extension</p>
  
  <pre><code>&lt;?php $this-&gt;Widget('ext.highcharts.HighchartsWidget', array(
     'options'=&gt;array(
          'title' =&gt; array('text' =&gt; 'Grafico a torta'),
          'chart' =&gt; array('renderTo' =&gt;'charts'),
          'credits' =&gt; array('enabled' =&gt; false),
          'series' =&gt; array (
              'type' =&gt; 'pie',
              'name' =&gt; 'name of serie',
              'data' =&gt; array (
                  array('Firefox', 44.2),
                  array('IE7', 26.6),
                  array('IE6', 20),
                  array('Chrome', 3.1),
                  array('Other', 5.4)
              ),
          ),
     )
  ));
  
  ?&gt;
  </code></pre>
  
  <p>It create this javascript </p>
  
  <pre><code>jQuery(window).on('load',function() {
  var chart = new Highcharts.Chart(
      {'chart':{'renderTo':'charts'},
       'exporting':{'enabled':true},
       'title':{'text':'Grafico a torta'},
       'credits':{'enabled':false},
       'series':{
             'type':'pie',
             'name':'name of serie',
             'data':[
                  ['Firefox',44.2000000000000028],
                  ['IE7',26.6000000000000014],
                  ['IE6',20],
                  ['Chrome',3.1000000000000001],
                  ['Other',5.4000000000000004]
             ]}});
  });
  </code></pre>
  
  <p>I'm not able to understand whats wrong.... no js error was throwed, not console debug info, nothing .... </p>
  
  <p>What I'm missing ?</p>