/**
* Write a string to standard error output.
*
* @param string $text The text to display.
* @param boolean $nl True (default) to append a new line at the end of the output string.
*
* @return AbstractCommand Instance of $this to allow chaining.
*
* @since 2.0
*/
public function err($text = '', $nl = true)
{
$this->io->err($text, $nl);
return $this;
}
