Jc/dst yaml upgrade

[unblockgames]

This modification does away with Tmux so that you can run this container using a yaml. This PR would require a rebuild of the image favoring the use of yaml to deploy container enabling support of common container orchestration such as portainer and other docker management tools.

[Catoverflow]

One of the reasons why I choose tmux is dst have 2 processes for master and cave world, and each of them have an interactive cli. If run in shell background that maybe not convenient enough to manage the servers?
I'm not very familiar with docker compose, is there any way to cope with the compose problems while maintaining both cli interactive? I'm also checking the compose part now.

[Catoverflow]

I had a discussion with @taoky . Generally we have 4 plans:
A. Current plan, use tmux/screen to detach/attach to manage master/cave world in a single container. Not orthodox but you can attach to master/cave cli and interact
B. Get away with tmux, use docker compose to run master/cave in different container. But we have duplication of 2 copies of steam cli and DST itself.
C. Your PR. But it's less manageable, you cannot attach to bg process as the shell hangs on wait -n
D. Get away with tmux, use socat and nc to manage master/cave (outside the container), but the context could be lost between nc and I think tmux/screen is better

All because DST's way of manage 2 worlds in different process is weird :(