Consider the case where you have a set of tagged / released images to
production, and you want to apply a small hotfix, security patch, etc.
to one of them, say keystone-ssh.
Rebuilding keystone-ssh will cause a rebuild of base, openstack-base,
and keystone-base, potentially pulling in updated packages / new
dependencies, unless you have access to the exact machine they were
previously built on. Ideally you want to use the exact parent images
that are in production.
This patch adds a new build argument '--skip-parents', which will result
in only the image(s) specified by the regex and their children to be
built. Parents are expected to exist either on machine or in a registry.
Change-Id: I79d5f0b422f48d2dc36ae85dfa21668cf8177837
Implements: blueprint image-build-depth
e5410950c4