statistics wrong release for stable/* branch

[ChangBo Guo(gcb)]

For example
cherry-pick to stable/mitaka was counted as stable/newton.

https://review.openstack.org/#/q/Idf5191aa1c990552ca2340856d5d5b6ac03f7539,n,z

And it appears in:
http://stackalytics.com/?metric=commits&project_type=tc-approved-release&release=newton&module=nova-group

Hironori Shiina (Fujitsu)
20 Sep 2016 04:08:36 UTC in nova
Commit “ironic: Cleanup instance information when spawn fails”
Instance information such as an instance_uuid set to an ironic node by _add_driver_fields() is not cleared when spawning is aborted by an
exception raised before ironic starts deployment. Then, ironic node stays AVAILABLE state with instance_uuid set. This information is not cleared even if the instance is deleted. The ironic node cannot be removed nor deployed again becuase instance_uuid remains.
This patch adds a method to remove the information. This method is called if ironic doesn't need unprovisioning when an instance is destroyed.
Change-Id: Idf5191aa1c990552ca2340856d5d5b6ac03f7539
Closes-Bug: 1596922
Commit date: 10 Jul 2016 06:32:58 UTC
+37 - 1