Fix doctrine common dependency

After release of Doctrine 2.4 the following versions was installed:
doctrine-orm: 2.3.x
doctrine-dbal: 2.3.x
doctrine-common: 2.4.x

We want the same version of doctrine components. I suggest blocking it on 2.3 for now.

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| License       | MIT