[QA][CI] Bump fuel-devops version up to 2.9.21

[Artem Panchenko]

We have a list of new bug fixes in the stable/2.9 branch of fuel-devops, some of them [0] are needed by our tests (blockers). So we need to bump fuel-devops version, test it on stable/mitaka qa code and if there is no regression - update fuel-devops version in the requiremets.txt. After that python venv on CI nodes must be updated.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: release/2.9
Review: https://review.openstack.org/325929

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/325931

[Aleksei Stepanov (penguinolog)]

Please wait for few cherry-picks:
1. ssh client
2. Allow create DB-independed libvirt networks from master

This will help for fuel-qa < 8.0

[OpenStack Infra (hudson-openstack)]

Change abandoned by Fuel DevOps Robot (<email address hidden>) on branch: master
Review: https://review.openstack.org/325931
Reason: This review is > 4 weeks without comment, and failed Jenkins the last time it was checked. We are abandoning this for now. Feel free to reactivate the review by pressing the restore button and leaving a 'recheck' comment to get fresh test results.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/325929
Committed: https://git.openstack.org/cgit/openstack/fuel-devops/commit/?id=2520d9a701a0623be102bbc8f1f28efd535336e0
Submitter: Jenkins
Branch: release/2.9

commit 2520d9a701a0623be102bbc8f1f28efd535336e0
Author: Artem Panchenko <email address hidden>
Date: Mon Jun 6 16:56:13 2016 +0300

    Bump fuel-devops version up to 2.9.21

    Change-Id: I90b4d4884914e0a5be914c1429dffef33a33e922
    Partial-bug: #1589515

[Aleksei Stepanov (penguinolog)]

Already 2.9.23