/**
 * Add a link to the output.
 *
 * @param   string  $key    The name of the link
 * @param   string  $value  The link
 *
 * @return  $this
 *
 * @since  4.0.0
 */
public function addLink($key, $value)
{
    $this->document->addLink($key, $value);
    return $this;
}