Add tags for 'prepare' and 'verify' stages to help the testing of OSM version...

Add tags for 'prepare' and 'verify' stages to help the testing of OSM version migration. New Keyword to get ns_id from NS name so that the tests with 'verify' tag can be executed in isolation.

Change-Id: I3f199146a8dbbe2f5f6aeb26a10b95440ee74470
Signed-off-by: rodriguezgar <frodriguezg@indra.es>