core: Update hibernate-validator version

Update hibernate-validator version to 4.2.0.Final in pom.xml according
to the run-time environment (JBoss-7.1.1.Final)

Change-Id: I6138000eba51c132f3362b874469c31ba45d642d
Signed-off-by: Yevgeny Zaspitsky <yzaspits@redhat.com>