fixed short trace and outside the class error

I got an exception if it was too short stack trace or if the logger not call inside of class.
The problem experienced with lf4php-monolog.
Try the other library, because I have not tried.

The way for error:
```php
$monologFactory = new \lf4php\monolog\MonologLoggerFactory();
$monologFactory->registerMonologLogger($monolog); // <-- instance of monolog
LoggerFactory::setILoggerFactory($monologFactory);
// call
LoggerFactory::getLogger('api')->error('Example Error!');
```
Thanks.