Refactor to fos user bundle approach.

[BernardoSilva]

• [x] Create root folder Doctrine
• [x] Move SSO StateStoreManager to src/AerialShip/SamlSPBundle/Doctrine/StateStoreManager.php
• [x] Move SSOStateDocument to src/AerialShip/SamlSPBundle/Doctrine/MongoDB/Document/SSOStateDocument.php
• [x] Rename SSOStateDocument to SSOState since its inside mongodb/document folder/namespace.
• [x] Move SSOStateEntity to ../Doctrine/Orm/Entity/SSOStateEntity.php
• [x] Rename SSOStateEntity to SSOState since its inside orm/entity folder/namespace.

This is inspered on https://github.com/FriendsOfSymfony/FOSUserBundle/tree/master/Doctrine suggested by @stof on https://github.com/aerialship/SamlSPBundle/pull/71#issuecomment-95113848

[stof]

The SSOStateEntity should not be in the Doctrine namespace: it is not tied to the Doctrine ORM at all. And there should be no SSOStateDocument at all. The same class should be used.

[BernardoSilva]

I think you can close this ticket as well @tmilos . With mongoDB PR we ended up refactoring the whole bundle :p