Proposal: Remove support for unused/under-tested stacks

[tobiasmcnulty]

To help reduce the maintenance burden of maintaining many stacks, I'd like to remove some of the stacks we don't use at Caktus any more.

If anyone in the community uses any of these and would like to help maintain them, please speak up!

The candidates for removal that initially come to mind are:

• Elastic Container Service (ECS): ECS has never felt like a good fit for any project that I can remember.
• Dokku: These days, it's probably better to use the EC2 stack and install Dokku manually or via Ansible oneself.

I'm on the fence about:

• Elastic Beanstalk (EB): It's nice to have a stack that supports containers but that doesn't involve the overhead of Kubernetes, but the second you need to run Celery or any other job, you're out of luck.

This would involve keeping (at least):

• Elastic Kubernetes Service (EKS)
• Elastic Compute Cloud (EC2)

I could imagine adding support for the recently-introduced container runtime for Lambda (https://aws.amazon.com/blogs/aws/new-for-aws-lambda-container-image-support/) at some point, which might provide a nice replacement for ECS, EB, and potentially Dokku as well.

What do others think? Would you like to see any of the proposed candidates for removal stay around, and how are they being used, if so?