Sahara always creates ResourceGroup for volumes even if that is not required

[Vitalii Gridnev]

Sahara always creates ResourceGroup for volumes even if node group template doesn't have volumes_per_node. It probably can cause validation errors during heat stack validations.

For example, in sahara-ci fake job for saharaclient, we can found that sahara creates 2 RG for volumes, but one of the node groups doesn't need any volumes for storage.

[Vitalii Gridnev (vgridnev)]

https://sahara.mirantis.com/logs/15/221115/2/check/gate-saharaclient-distributed-heat-fake/b23cb4b/sahara-log-engine-2.txt

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/220538
Committed: https://git.openstack.org/cgit/openstack/sahara/commit/?id=2b25dfa07fedbbe48cc4f92e9ab1933f87101488
Submitter: Jenkins
Branch: master

commit 2b25dfa07fedbbe48cc4f92e9ab1933f87101488
Author: Vitaly Gridnev <email address hidden>
Date: Fri Sep 4 17:46:55 2015 +0300

    Create ResourceGroup with volumes only if it is required

    If volumes_per_node or volumes_size is 0, there is no sense
    in creating empty ResourceGroup.

    Also remove volumes from one node group in gate to be sure
    that sahara correctly handle such case.

    Closes-bug: 1494650
    Change-Id: Ic592710773b9338f5857e431b0567bc5c87af2bd

[Vitalii Gridnev (vgridnev)]

Reopened bug

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/245445
Committed: https://git.openstack.org/cgit/openstack/sahara/commit/?id=faef6379cb1f7ba0ec70dfcbcb61c8d60b17518a
Submitter: Jenkins
Branch: master

commit faef6379cb1f7ba0ec70dfcbcb61c8d60b17518a
Author: Vitaly Gridnev <email address hidden>
Date: Sat Nov 14 22:14:08 2015 +0300

    Remove unneeded volume serialization

    It looks like this serialization introduced
    because of some rebase, anyway it's clear that
    it's unneeded.

    Closes-bug: 1494650
    Change-Id: If0140ca9f22fb3073fafccada512c877322efc2d

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/liberty
Review: https://review.openstack.org/248101

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/248101
Committed: https://git.openstack.org/cgit/openstack/sahara/commit/?id=a6b3a8803e92e08f3fc65f59a64221419661c2b4
Submitter: Jenkins
Branch: stable/liberty

commit a6b3a8803e92e08f3fc65f59a64221419661c2b4
Author: Vitaly Gridnev <email address hidden>
Date: Sat Nov 14 22:14:08 2015 +0300

    Remove unneeded volume serialization

    It looks like this serialization introduced
    because of some rebase, anyway it's clear that
    it's unneeded.

    Closes-bug: 1494650
    Change-Id: If0140ca9f22fb3073fafccada512c877322efc2d
    (cherry picked from commit faef6379cb1f7ba0ec70dfcbcb61c8d60b17518a)