title: XmlSlurper.parse(uri) with HTTP basic authentication
body: <p>I need to grab a data from XML-RPC web-service.</p>
  
  <p><code>new XmlSlurper().parse("http://host/service")</code> works fine, but now I have a particular service that requires basic HTTP authentication.</p>
  
  <p>How can I set username and password for <code>parse()</code> method, or modify HTTP headers of the request?</p>
  
  <p>Using <code>http://username:password@host/service</code> doesn't help - I still get <code>java.io.IOException: Server returned HTTP response code: 401 for URL</code> exception.</p>
  
  <p>Thanks</p>