add support for user id in keystone cadf events

[Steve Martinelli]

as of kilo, keystone now allows a deployer to emit 'cadf' notifications instead of the standard notifications for most CRUD operations. as a result, the user_id that initiated the request is now available if 'cadf' is selected as the notifications format.

ceilometer may be updated to check for a user id in the initiator payload of the notification.

[Steve Martinelli (stevemar)]

patch to address the issue: https://review.openstack.org/#/c/151524/

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/151524
Committed: https://git.openstack.org/cgit/openstack/ceilometer/commit/?id=885b97faadbef94b8a9d47badc6ace271fcae478
Submitter: Jenkins
Branch: master

commit 885b97faadbef94b8a9d47badc6ace271fcae478
Author: Steve Martinelli <email address hidden>
Date: Thu Jan 29 22:36:23 2015 -0500

    Attempt to set user_id for identity events

    Since the Keystone team will be moving to CADF events, where the
    initiator is included, we should attempt to retrieve the id if
    it's available.

    Closes-Bug: 1429339

    Change-Id: Ia5c3723cdb587aa87c3e3083c03c9de3f799772b