title: get "onclick" url value with nokogiri
body: <p>The <code>anchor</code> variable content this link:</p>
  
  <pre><code>anchor = &lt;a href="javascript:void(0);" class="cvt-nowrap" onclick="javascript:window.open('http://url.com/persona/WebLinkEntryPoint.php?idowner=36054&amp;amp;code=DetalleOferta&amp;amp;idofe=140543&amp;amp;no_links=true', '', 'left=10, top=10, width=1200, height=860, resizable=yes, scrollbars=yes, menubar=no, toolbar=no, directories=no, location=no, status=no'); return false;"&gt;&lt;img src="http://static.cvtools.com/public/static/abantia/images/2013-04-02-11-14-50.7705_link.gif" border="0" align="absmiddle"&gt;Here text&lt;/a&gt;
  </code></pre>
  
  <p>I'm using <a href="http://nokogiri.org/" rel="nofollow">nokogiri</a> gem and I would like to know if is possible extract the next url for this link:</p>
  
  <pre><code>http://url.com/persona/WebLinkEntryPoint.php?idowner=36054&amp;code=DetalleOferta&amp;idofe=140544&amp;no_links=true
  </code></pre>