Collecting Update requirements and use-cases for the working group.

We should be able to update a running container. There are a few simple updates like resources for vertical scaling of containers (memory, cpu) that should be allowed. Adding a volume is another possible use-case.

Do we split the config into immutable and mutable parts? The updates can be done out of band, but we would like the config to reflect reality of the running state.

Hopefully, we can collect more requirement and concerns before handing it over to a working group.