Correct JCA module's build

The recently added "modeshape-jca" module has several things that need to be changed:

• it should not overwrite the maven-compiler-plugin, maven-rar-plugin and maven-jar-plugin versions and JDK version (1.5 vs. 1.6), but should inherit them from jboss-parent via modeshape-parent.
• it should not overwrite the maven-jar-plugin from what's in modeshape-parent & jboss-parent ?
• all its dependencies & version properties should go in modeshape-parent, in the <dependencyManagement> section, just like all the other modules
• it should have an "assembly" profile so that we can distribute it along with the other modules (via -Passembly). The packaged RAR also needs to be included in the binary assembly.