All provider specific settings have been moved to the
provider section. The image name itself is now located
at the top level and called "name". It is required for all providers.
Although it isn't yet deprecated by the wiki[1], the Debian mirrors HTTP
redirector names itself as `httpredir.debian.org`, even when accessed at
`http.debian.net`.
[1]: https://wiki.debian.org/DebianGeoMirror