Merge url_with_address into master

The hostname to query for requests is passed explicitly in the request itself. This allows to swap between different server instances easily for tests. Note that when deploying this version of the script you need to pass a hostname and not just an IP address because 'magento.hostname' will be used as the URL to query the packaged product names. 'magento.hostname' has to be reachable too, if there is no DNS entry you need to add an entry in the /etc/hosts file for it.