Proactively check for when Docker has broken dvm

[carolynvs]

We need to automate checking that dvm still works for the latest stable, prerelease and edge releases.

• Install an old uncompressed version (e.g. 1.8.0)
• Install an old compressed version (e.g. 1.11.0)
• Install an old compressed version with the new naming scheme (e.g. 17.05.0-ce)
• Install a "new" version (e.g. 17.06.0-ce)
• Install a "new" prerelease version (e.g. 17.07.0-ce-rc2)
• Install the latest edge version and somehow tell that it's really the latest edge
• Install the latest stable version, and somehow tell that it's really latest (do we trust github releases anymore?)