Should we optimize the CircleCI Docker images further?

[jasonmp85]

It's unclear to me whether it's worth the readability tradeoff to inline our shell scripts directly into our Dockerfiles… on one hand, having fewer layers will shrink them somewhat, but perhaps it might be sufficient to use something like the new official --squash flag (still experimental, I believe), first discussed in this blog post from around two years ago.

Whoever performs this task should also poke around the layer diffs to see whether we're missing any low-hanging fruit we can knock off at the same time.

[jasonmp85]

Things to read from the Docker Documentation:

• Best practices for writing Dockerfiles
• Docker object labels