Add docker compose deployment handler

[mew1033]

I'd like to use the SSH deploy method, but deploy an entire docker compose file with potentially multiple containers. I can probably start adding this myself, but I want to ask where this would fit. Would you like an additional option in image:? Potentially something like ssh-compose? Or would you prefer an entirely new deployment handler? I envision this process as follows:

1. Use subprocess to rsync-over-ssh the entire challenge folder to the remote server. Use the same slugify-d name as the directory name on the remote server.
2. SSH to the remote server and run docker compose up -d in the target directory. Let docker handle all the building/deploying on the remote server.