* [upcloud] add option to use preconfigured cpu/mem plan

* [upcloud] add option to use firewall rules for API server/SSH access

* [upcloud] add option to use managed load balancer

* [upcloud] add upcloud csi-driver

* Option to use ansible_host as api ip for kubueconfig

additional disks

* rename ansible groups to use _ instead of -

k8s-cluster -> k8s_cluster
k8s-node -> k8s_node
calico-rr -> calico_rr
no-floating -> no_floating

Note: kube-node,k8s-cluster groups in upgrade CI
      need clean-up after v2.16 is tagged

* ensure old groups are mapped to the new ones

This replaces kube-master with kube_control_plane because of [1]:

  The Kubernetes project is moving away from wording that is
  considered offensive. A new working group WG Naming was created
  to track this work, and the word "master" was declared as offensive.
  A proposal was formalized for replacing the word "master" with
  "control plane". This means it should be removed from source code,
  documentation, and user-facing configuration from Kubernetes and
  its sub-projects.

NOTE: The reason why this changes it to kube_control_plane not
      kube-control-plane is for valid group names on ansible.

[1]: https://github.com/kubernetes/enhancements/blob/master/keps/sig-cluster-lifecycle/kubeadm/2067-rename-master-label-taint/README.md#motivation

* terraform support for UpCloud

* terraform support for UpCloud

* terraform support for UpCloud

* terraform support for UpCloud

* terraform support for UpCloud

* terraform support for UpCloud

* terraform support for UpCloud

* Updates to README.md and main.tf files

* formatting and updating readme

* added a .terraform_validate CI job

* fixed format issue

* added sample inventory

* added symbolic link to group_vars

* added missing tf variables and minor fixes

* added text formatting

* minor formatting fixes