Update OpenStack release detection
Update OpenStack release detection

Change-Id: Icad13836d88583ee676525d4743f12a5b888ebe2
Signed-off-by: Cédric Ollivier <d48310251a4a484d041bc5d09a9ac4d86d20f793@orange.com>

opnfv/functest,opnfv/functest