This patch sets URL to glance worker.
If this is set, other glance workers will know how to contact this one
directly if needed. For image import, a single worker stages the image
and other workers need to be able to proxy the import request to the
right one.
With current setup glance image import just not working.
Closes-Bug: #2048525
Change-Id: I4246dc8a80038358cd5b6e44e991b3e2ed72be0e
9ecfcf5a17