title: XPath: select nodes with explicit 'xmlns' attribute
body: <p>Could anyone please provide XPath expression which selects all nodes that have explicit 'xmlns' attribute, e.g. <code>&lt;html xmlns="http://www.w3.org/1999/xhtml"&gt;</code>? <code>//*[@xmlns]</code> does not work because (as it turned out) xmlns is not treated as attribute by XPath.</p>
  
  <pre><code>&lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"&gt;
  &lt;html xmlns="http://www.w3.org/1999/xhtml"&gt;
  &lt;head&gt;
  &lt;meta http-equiv="X-UA-Compatible" content="IE=edge"/&gt;
  &lt;title&gt;Информация по счетам, картам&lt;/title&gt;
  &lt;meta http-equiv="Content-Type" content="text/html; charset=utf-8"/&gt;
  &lt;meta http-equiv="cache-control" content="no-cache"/&gt;
  &lt;meta http-equiv="pragma" content="no-cache"/&gt;
  .......
  </code></pre>
  
  <p>I need only 'html' node here.</p>