The zuul v3 architecture does not require that this be supported
as an internal special case. Remove it for now in the expectation
that we will implement similar functionality using the auth system
and Ansible roles.
Change-Id: I9c1e05a716ce8cfb5f66c4688db110c320d33b4b
Have zuul send signed credentials as part of the job for workers to
consume and upload assets to a defined location.
Zuul currently doesn't care about logs however this change will
suggest a LOG_PATH to builders as a unqiue destination prefix
allowing zuul to know preemptively the destination.
The workers are still required to send a URL of the final location.
Change-Id: I042cdd2dd2407f381cafcabc5c6b83d9b9a9eb00