Support docker-compose process debug

[qhsong]

Cloud and Container is popular for developing but some C++ programmer now debugging via print logs. It is hard to use debugger in some scenarios:
* Program need depends other components, such as Kafka/Zookeeper/Redis etc, running program in local is hard working
* Program need running in cluster mode, one program may have multiple processes in different container, debugging those processes is hard.

So I think support debugging in containers is a good way to solve. vscode Node.js/Python debug plugin is already support it via network development, so use lldb-server may good way.

Here is my plan:
* User write docker-compose.yml define running env and launch process via lldb-server and expose debug port for processes
* vscode-lldb can attach some processes and debug them ( debugging in multiple processes in one editor may hard for UI, but user can open multiple vscode to debug)
* After finish debug, docker-compose stop all containers and clean docker-images

I think this maybe a killing feature for debugger.

[vadimcn]

Hi @qhsong,
This sounds like a good plan, but what do you want to change about the extension? I think all you want to do is already possible:

• You can use preLaunchTask and postDebugTask to start containers before a debug session, and shut them down afterwards.
• CodeLLDB already supports remote debugging.
• You can use compound launch configurations to start multiple debug sessions at once.

I suppose one could desire to automate creation of all of these config files, but that can be accomplished by an external script.

Also, if you are content with debugging each process in a separate windows, you could just use VSCode Remote Development.

[qhsong]

Maybe this plan is not well considered currently and thanks give me those docs, I will try it.
After that maybe we can have future discuss.