title: Get attributes values from select2 selected option
body: <p>I'm using the Select2 plugin from <a href="http://ivaynberg.github.io/select2/select2-latest.html" rel="noreferrer">http://ivaynberg.github.io/select2/select2-latest.html</a> what works fine but i'm having a problem to get the values from the options attributes.</p>
  
  <p>I've got a select menu like this:</p>
  
  <pre><code>&lt;select name="invoice_line[0][vat]" class="vat"&gt;
      &lt;option value="20440" data-value="21.00" data-name="20440" selected="selected"&gt;21%&lt;/option&gt;
      &lt;option value="20441" data-value="6.00" data-name="20441"&gt;6%&lt;/option&gt;
      &lt;option value="20442" data-value="0.00" data-name="20442"&gt;0%&lt;/option&gt;
  &lt;/select&gt;
  </code></pre>
  
  <p>How can I get the values of the attributes 'data-value', 'data-name' and 'value' of the selected option?</p>