title: Creating XDocument with xsi:schemaLocation namespace
body: <p>I need to create the following XML and I'm trying to do this using XDocument. However, I'm having trouble specifying the name spaces.</p>
  
  <pre><code>&lt;AssessmentOrderRequest
      xsi:schemaLocation="http://ns.hr-xml.org/2007-04-15 http://ns.hr-xml.org/2_5/HR-XML-2_5/StandAlone/AssessmentOrderRequest.xsd"
      xmlns="http://ns.hr-xml.org/2007-04-15"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"&gt;
  &lt;/AssessmentOrderRequest&gt;
  </code></pre>
  
  <p>This is the sort of code that I'm looking for, however, I can't create attributes with a colon in the name for the <code>xsi:schemaLocation</code>.</p>
  
  <pre><code>return new XDocument(
      new XElement("AssessmentOrderRequest",
          new XAttribute("xsi:schemaLocation", XNamespace.Get("http://ns.hr-xml.org/2007-04-15 http://ns.hr-xml.org/2_5/HR-XML-2_5/StandAlone/AssessmentOrderRequest.xsd")),
          new XAttribute("xmlns", XNamespace.Get("http://ns.hr-xml.org/2007-04-15")),
          new XAttribute(XNamespace.Xmlns + "xsi", XNamespace.Get("http://www.w3.org/2001/XMLSchema-instance"))
      )
  );
  </code></pre>