Document software choices with rationale

[daachi]

This task will be for considering some of the basic software components to support a fairly basic Kubernetes deployment working such that we can deploy to it in a fairly standard way.

As we go along, any additional software components we discover that may become part of our desired configuration will be taken up in follow-on tickets/tasks.

[daachi]

For operating system, at this point we're just saying RHEL8 because that's what we have the infrastructure in place to support.

For Kubernetes we will use the OSS OKD since it is the downstream, open source version of Red Hat's OpenShift ( i.e. their Kubernetes ).

Other software, or perhaps services, are ArgoCD for deployment. This is an industry standard.

For LMA ( Logging, Monitoring and Alerting ) aka. Observability, we'll use kube-prometheus. Again, this is a standard choice.