docker.io name is not discoverable (obsolete)

[Philippe Cloutier]

This package uses the name "docker.io", which apparently refers to docker-io, an obsolete executable it previously contained: https://stackoverflow.com/questions/45023363/what-is-docker-io-in-relation-to-docker-ce-and-docker-ee
Docker - whatever that means - is a mysterious thing and I don't know what exactly this package contains nor what would be an optimal name, but for sure the current name should be changed.