The ubuntu base image is now also available on dockerhub in the ubuntu
namespace[0]. So allow using the tag-images.sh script with the
dockerhub registry.
software-versions.sh: Look up the package versions in docker images
Determine the docker image names for the software packages and attempt
to download them locally. If that succeeds, create a temporary
container and run it to look up the installed version of the software.
Previously we used a binary metapackage to help determine the source
package name for a given Ubuntu release. The installed binary package
we're looking at in the image is not necessarily the same as the
metapackage, and in some cases its name is versioned like the source
package. So, for example with mysql we have 'mysql-{M.N}' as the source
package, 'mysql-server' as the metapackage used to determine M.N, and
then 'mysql-server-core-{M.N}' as the installed binary package we're
looking up.
shellcheck flagged some lines as needing quoting that actually need to
not have quoting because we are intentionally using that behavior for
dividing up the parts of a version number.
Restore the original quoting and add a shellcheck disable.
The sync-multiarch-images.sh script copies an image from one registry to
another (by pulling and then pushing the image). Optionally, the user
can specify the architecture of the image being moved over. Additionally
the script runs a simple smoke test with the pulled image to make sure
the image being moved over is sane and was built for the requested
architecture.
