Extended audit criteria api with the ability to traverse associations

Extended the audit query API such that criterias, orders and projections can be expression accross to-one associations. This works currently for "entities at revision" and "entities modified at revision" queries but not for "revisions of entity" queries. The latter is also possible and can be implemented in the future.

The basic idea to enable audit queries accross to-one associations is that a full join of the association entity is made and original id and the correct revision is filtered in the "where" part of the HQL query.