Support groups of nodes with a disctinct set of labels and taints (node groups)

[corvus-ch]

Summary

As a solution engineer
I want to be able to provision cluster with mixed worker node sizes
So that I can implement the customer's requirements

Context

Modify Terraform module to support mixed worker node types and document how to migrate existing cluster Terraform states to the new module version.

Further links

• Related issue for OCP4 Exoscale Terraform module: Support groups of nodes with a disctinct set of labels and taints (node groups) terraform-openshift4-exoscale#15

Acceptance criteria

• OCP4 clusters on cloudscale.ch with mixed worker node sizes can be provisioned by Terraform

Implementation Ideas

1. Change Terraform module to accept worker group configuration as map of worker group name to worker group parameters (instance type, disk size, etc.) and instantiate the internal node-group module for each entry

[simu]

Implemented in #25