public function addTarget($target, array $config)
{
$ext = $this->getExt($target);
$config += ['files' => [], 'filters' => [], 'theme' => false, 'extend' => false, 'require' => []];
if (!empty($config['paths'])) {
$config['paths'] = array_map(array($this, '_replacePathConstants'), (array) $config['paths']);
}
$this->_targets[$target] = $config;
}