Inject an attribute metadata driver into the DoctrineDriver when testing

[mbabker]

Q	A
Bug fix?	no
New feature?	no
Doc updated	no
BC breaks?	no
Deprecations?	no
Tests pass?	yes
Fixed tickets	Partially #1516
License	MIT

Another small test change that will help with the ORM 3.0 compat. Without its classes having the @Annotation annotation anymore in 3.0, there are a lot of Doctrine\Common\Annotations\AnnotationException: [Semantical Error] The class "Doctrine\ORM\Mapping\Entity" is not annotated with @Annotation. style exceptions being thrown. Changing the DoctrineDriverTest to have version conditional behavior and use an annotation or attribute driver as appropriate clears out some of those.

Merging #1471 will help address this in other places in the tests at a later point, but with the hard dependency still in place, those other test classes are not yet updated.

[scyzoryck]

Looks good for me! I will merge it on the beginning of the next week with other related PRs. :)