I'm trying to create `Configuration`:

`$config = new \Doctrine\ORM\Configuration;`

Although I can see this class using `Open declaration` in Zend Studio running it in browser results in:

`Fatal error: Class 'Doctrine\ORM\Configuration' not found in C:\Program Files\Zend\Apache2\htdocs\MyProject\library\Custom\Entitymanager.php on line 20`