Allow url to be updated
Allow url to be updated

Allow a gearman worker to send extra WorkData packets to update the
url as it makes progress.

Change-Id: I29ce3fbc83bedf2d49657560c9a0c88d8ab38b35

gooddata/zuul,gooddata/zuul,wikimedia/integration-zuul,wikimedia/integration-zuul,gooddata/zuul,devdattakulkarni/zuul_messaging,gooddata/zuul,devdattakulkarni/zuul_messaging,wikimedia/integration-zuul,gooddata/zuul,wikimedia/integration-zuul,devdattakulkarni/zuul_messaging