Comment 2 for bug 1768604

Reviewed: https://review.openstack.org/565846
Committed: https://git.openstack.org/cgit/openstack/python-tripleoclient/commit/?id=c0b7bad64e34a2a5b6ab19ca09ec15655541dc84
Submitter: Zuul
Branch: stable/queens

commit c0b7bad64e34a2a5b6ab19ca09ec15655541dc84
Author: Tony Breeds <email address hidden>
Date: Mon Dec 18 12:22:24 2017 +1100

    Add --validate-only to openstack overcloud node import

    Previously there was 'openstack baremetal instackenv validate' to
    quickly validate an environment file.

    Much of which is now done in the validate_nodes mistral workflow. Add a
    mode to cease operations after validating the environment file

    Note on the backport:
    The old command was removed in Queens, so we need to backport this
    new flag to fill in the gap. The workflow was introduced in Pike.

    Closes-Bug: #1768604
    Change-Id: Ie2bfc79b45f4652285718be34a5e07ce5777c60d
    (cherry picked from commit ebc64b681cbd0e760d34b1dcc268f3b487a051e8)