Return blueprint version or path to the image at the end of builder role

[empovit]

When building an OS image (installer, simplified installer, qcow2, etc.) using the builder role, the resulting image can be found in the /var/www/html/<blueprint_name>/images/<version>/ directory or downloaded from http://<host>/<blueprint_name>/images/<version/. The problem is that the collection doesn't provide a way to know the version. Possible solutions would be to return the current version of the blueprint being built, or the entire download URL.