Use a tagged version of fluo-dev or a commit

[keith-turner]

Looking at the docker file it seems like its using some branch of fluo-dev called download-refactor. AFACIT this branch does not exists, what am I missing here?

It would be nice to use a tag or specific commit hash of fluo-dev. Thinking this would make using this docker file more stable over time.

[drewfarris]

In my haste, I didn't clean things up in the Dockerfile wrt the branch. I was originally depending on a branch from @mikewalch, and removed the explicit branch argument to the clone when I switched to the @fluo-io version. I'll push a change to simply use master for the time being until I come up with something better.