Docker: Remove All Images and Containers

I've moved to a new project at Mozilla which uses a much different stack than I'm used to; suddenly I'm thrust into a world of Mercurial, Docker, and a few other technologies I'm not accustomed to.  You know what that leads to:  foul language, frustration, booze, and...lots of starting over.  Some hate starting over but wiping the slate clean provides me a bit of ease, knowing that I'm not compounding the problem by trying to patch a fix of a shim.

Starting over in this case means wiping clean my Docker images and containers, just to make sure there are no conflicts or duplicates.  The following commands delete all containers and images:

# Delete every Docker containers
# Must be run first because images are attached to containers
docker rm -f $(docker ps -a -q)

# Delete every Docker image
docker rmi -f $(docker images -q)

Of course you don't want to do this if you're using Docker across multiple projects -- you'll find yourself in a world of hurt if you break your other images and containers.

There you have it -- a clean Docker slate in one pass!