Add a proper exception when Doctrine ORM is not installed
Add a proper exception when Doctrine ORM is not installed

fabpot/DoctrineBundle,mikeSimonson/DoctrineBundle,nicolas-grekas/DoctrineBundle,fabpot/DoctrineBundle,fervo/DoctrineBundle,mikeSimonson/DoctrineBundle,doctrine/DoctrineBundle,gencer/DoctrineBundle,hason/DoctrineBundle,OskarStark/DoctrineBundle,hason/DoctrineBundle,fervo/DoctrineBundle,OskarStark/DoctrineBundle,gencer/DoctrineBundle,nicolas-grekas/DoctrineBundle