public static function getInstance($cfg = array())
    {
        if (!isset(self::$instance)) {
            return false;
        } elseif ($cfg) {
            self::$instance->setCfg($cfg);
        }
        return self::$instance;
    }
public static function getInstance($cfg = array())
    {
        if (!isset(self::$instance)) {
            return false;
        } elseif ($cfg) {
            self::$instance->setCfg($cfg);
        }
        return self::$instance;
    }
Returns the *Singleton* instance of this class (IF INSTANCE EXISTS)

@param array $cfg optional config

@return object|false