def _append_asset!(xml, asset)
      if asset.is_a? Nexpose::IPRange
        xml.add_element('range', 'from' => asset.from, 'to' => asset.to)
      else # Assume HostName
        host = REXML::Element.new('host')
        host.text = asset
        xml.add_element(host)
      end
    end
def _append_asset!(xml, asset)
      if asset.is_a? Nexpose::IPRange
        xml.add_element('range', 'from' => asset.from, 'to' => asset.to)
      else # Assume HostName
        host = REXML::Element.new('host')
        host.text = asset
        xml.add_element(host)
      end
    end
Utility method for appending a HostName or IPRange object into an
 XML object, in preparation for ad hoc scanning.

 @param [REXML::Document] xml Prepared API call to execute.
 @param [HostName|IPRange] asset Asset to append to XML.