Updated to work with Universal Analytics (analytics.js)

Works with new Universal analytics, using the 

ga('ecommerce:addTransaction', {
  'id': '1234',                     // Transaction ID. Required
  'affiliation': 'Acme Clothing',   // Affiliation or store name
  'revenue': '11.99',               // Grand Total
  'shipping': '5',                  // Shipping
  'tax': '1.29'                     // Tax
});

Method from 
https://developers.google.com/analytics/devguides/collection/upgrade/reference/gajs-analyticsjs

Must add your own tracker to the header 

 ga('create', 'UA-xxxxxxxx-x', 'xxx.com');
  ga('send', 'pageview');
  ga('require', 'ecommerce', 'ecommerce.js');   // Load the ecommerce plug-in.