Possible Changes #3
Description
I really like the idea of this project but I had a few things that I wanted to adjust about it but since they're relatively significant changes I wanted to ask before I worked on them. Let me know what you think and I'll work on PR's for the changes you feel comfortable with.
Docker Image Selection
Some users may want to select which Docker image they want their app to run in. This would be a nice little addition to give some more flexibility.
Shell Command
If you had a Docker container that you needed to make changes to it would be nice to be able to easily connect to the container. I know that in theory you could just use docker ps to find the container and then docker exec -it <container> bash to connect to it but it would be nice to have an easy to just say cage app:shell to connect to the container directly.
An example of why this would be useful is for dealing with Python libraries that require C libraries to be installed.
Switch to Click
Click is a command line parsing library that aims to be simpler and more powerful than argparse. It's a much nicer developer experience in my opinion.