Provide documentation for easily setting up self-hosted S3-compatible storage

[dmcc]

This could use Ceph or any other implementation, ideally as a Docker container and/or Docker Compose configuration (i.e., so it composes nicely with https://github.com/quant-aq/aeromancy/issues/16).

[dmcc]

This turns out to be fairly easy to do with min.io. Some notes from the setup until we can add them to docs:

• The install command from min.io on dockerhub seemed fine. If you're running docker, it's:

  docker run -p 9000:9000 -p 9001:9001 -v /where/to/store/data/locally:/data \
    quay.io/minio/minio server /data --console-address ":9001"

  where /where/to/store/data/locally will be the root of where min.io stores data.

• Once installed, you can create an access key through the web UI by going to http://localhost:9001
  • Login with username minioadmin and password minioadmin
  • Go to http://localhost:9001/access-keys/new-account
  • Set the access key's name to Aeromancy (or whatever you'd like to call it) and fill in Description and Comments if you like. Other defaults should be fine.
  • The Access Key should be stored in the environment variable AEROMANCY_AWS_ACCESS_KEY_ID and Secret Key should be stored in AEROMANCY_AWS_SECRET_ACCESS_KEY
• Lastly, we need to set an endpoint. If your IP address is 192.168.1.23, then set the environment variable AEROMANCY_AWS_S3_ENDPOINT_URL to http://192.168.1.23:9000