Module dependency to Hibernate Search should use slot version 5.0

As discussed on the mailing list:
http://lists.jboss.org/pipermail/infinispan-dev/2014-September/015390.html

as we otherwise get a duplicate version of hibernate-search-engine on the classpath when people intend to use Infinispan modules to store Search indexes generated by an Hibernate Search "normal" distribution.

Also integration tests of Infinispan should download and use the Hibernate Search distribution of its modules for WildFly, rather than bundling custom ones.