integrate hibernate-envers

hibernate-envers now is part of hibernate-core, which provides auditing/versioning function for entities.

it is well used by the hibernate community, so AS 7 should (consider) integrate it.
thanks to org.hibernate.integrator.spi.Integrator, envers can be automatic enabled if the user's application has @Audit annotation and envers jar is on the classpath with hibernate-core. (which also means application classloader needs to see envers class)

p.s. i'm setting the fix version to 7.0.0.CR1 here, just because i'd really like it goes into this release, and i would like help as much as i can to make it happen, but feel free to remove it if this can't happen

Steps to complete task:

1. Create a "org.hibernate.envers" module by creating a module.xml in as7/build/src/main/resources/modules/org/hibernate/envers/main.
To get an idea of what this looks like, first see as7/build/src/main/resources/modules/org/hibernate/main/module.xml contents and model the new module after one of the current modules listed there (perhaps org.javassist). org.javassist is in as7/build/src/main/resources/modules/org/javassist/main).

2. Update as7/build pom.xml and build.xml for envers

3. Update as7/pom.xml adding in version information for the new artifact (should be able to use Hibernate version def unless envers has its own version)

4. If you build AS7, the envers jars should end up in as7/build/target/jboss-7.0.0.Beta4-SNAPSHOT/modules

5. Next, add the "org.hibernate.envers" dependency to the "org.hibernate" module (in as7/build/src/main/resources/modules/org/hibernate/main.xml)

I'll add further steps for adding a unit test after you reach this far.