* Use name+number as the build identifier for all meta-jobs.
(Zuul has name + number as build metadata, so avoid adding new/duplicate
features).
* Refer to the name of the manager worker as 'manager' instead of 'master'
to avoid jenkins specifics.
* Just call the url "url" instead of "full_url".
* Change SetDescriptionWorker to use name+number as the build id.
Also, expect 'html_description' instead of 'description'.
* Don't catch as many exceptions, instead, let them propogate so that they
get turned into WORK_EXCEPTION packets with information (instead of
WORK_FAIL packets which have no info).
* Change StopJobWorker to use the same name+number interface as
setDescriptionWorker (for consistency, expandability, plus it makes
the code simpler).
Change-Id: I8e078540c252bf9c1f14b79f8182517cbaa13555