title: is it possible to send custom variables to Google analytics while using ecommerce extension
body: <p>So basicly i'm trying to get custom variables trough to google analytics panel while using ecommerce extension. My main goal is to give every item a set of custom values.</p>
  
  <p>My "code" looks like this: </p>
  
  <pre><code>ga('require', 'ecommerce');
  ga('ecommerce:addTransaction', {
      'id': 'id',                     
      'affiliation': 'affiliation',  
  });
  ga('ecommerce:addItem', {
      'id': 'id',
      'name': 'Loan  - name',
      'sku': '{RIDA:success_loan_id}',
      'loanSumEur': 'Sum',
      'loanSumLit': 'Sum LTL',
      'loanLength': 'length',
      'loanData': 'data'
  });
  ga('ecommerce:send');
  ga('ecommerce:clear');
  </code></pre>
  
  <p></p>
  
  <p>How should I declare those loanSumEur, loanSumLit, loanlength, loanData variables so Google would pass them trough to the google analytics admin panel. Is it even possible ? </p>
  
  <p>It's quite easy to declare custom variables for site tracking, however I got a little bit stuck trying to do the same thing on transaction items. </p>
  
  <p>BR's</p>