Re-added config.version to config-module-archetype.

Fix broken archetype that failed to generate valid poms.
Since the archetype's generated pom can live in hierarchy
different from ODL, the template must specify version
of config-api same as it does for plugins.

Change-Id: I88bb7db303395c82f389af90c668efe563cb3bdb
Signed-off-by: Tomas Olvecky <tolvecky@cisco.com>