* Add a new variable UPGRADE_BASEBRANCH and use that to check out a
stable branch, then run the bootstrap process. This will require a
change to project-config so that the job names will add in the branch
name, so we can pick it up instead of providing a value when none is
present.
* Add a section to confd_overrides for the upgrade scenario to fix the
following error
TASK [bootstrap-host : Deploy user conf.d configuration] ***********************
fatal: [localhost]: FAILED! => {"failed":
true, "msg": "{{ confd_overrides[scenario] }}: 'dict object' has no
attribute u'upgrade'"}
Change-Id: Ia5fd197e81da0a1fd55327d155f181c8792bc199
3c8548b265