/**
* Return combined minified content for a set of sources
*
* No internal caching will be used and the content will not be HTTP encoded.
*
* @param array $sources array of filepaths and/or Minify_Source objects
*
* @param array $options (optional) array of options for serve. By default
* these are already set: quiet = true, encodeMethod = '', lastModifiedTime = 0.
*
* @return string
*/
public static function combine($sources, $options = array())
{
$cache = self::$_cache;
self::$_cache = null;
$options = array_merge(array('files' => (array) $sources, 'quiet' => true, 'encodeMethod' => '', 'lastModifiedTime' => 0), $options);
$out = self::serve('Files', $options);
self::$_cache = $cache;
return $out['content'];
}