enable validation and reconciling for annotation-defined repositories

At the moment we support validation and reconciling for interfaces that extend the Spring Data repository class, but it fails when the repository is defined via annotations (see http://blog.springsource.org/2011/07/27/fine-tuning-spring-data-repositories/ for an example). The major problem is the definition of the domain class in the annotation instead of the super interface generic type.

We need to add support for this.