[FELIX-4370] Additional work to support the OSGi Repository Service.

Improved the mapping between OBR and OSGi namespaces.
This also fixes an OSGi Repository CT failure:
  RepositoryTest.testRepositoryContent()


git-svn-id: https://svn.apache.org/repos/asf/felix/trunk@1591679 13f79535-47bb-0310-9956-ffa450edef68