---
features:
  - |
    Individual playbooks may now be wrapped by a semaphore.  Zuul will
    start the job and proceed up to the point of a playbook which
    requires a semaphore and then wait until it is able to aquire the
    semaphore before proceeding.  It releases the semaphore after the
    end of that individual playbook.

    The same semaphore may be used for both jobs and playbooks, but an
    individual job may not use the same semaphore for both purposes.