tf-elax_ubuntu18-calico is so flake today. The test job is failed
due to SSH connectivity check error after deploying virtual machines
which are used for Kubernetes nodes.
This allows failure on the job to see the test situation without
pull request merger failures.

When running the script, I faced the following error but it was
difficult to know the root problem due to lack of error handling.

  docker tag" requires exactly 2 arguments.
  See 'docker tag --help'.

  Usage:  docker tag SOURCE_IMAGE[:TAG] TARGET_IMAGE[:TAG]

  Create a tag TARGET_IMAGE that refers to SOURCE_IMAGE

To investigate such errors easily, this adds an error handling.

* csi-driver: Added possibility to use application credentials for cinder

* external-cloud-controller: Added env vars for openstack application credentials

* set selinux type t_etc if selinux state is enforcing

* workaround with update repo is no longer needed
remove comments about failing playbook

* grubby is not available in distros using ostree

* remove docker support because removed in fcos
update install script example with live rootfs

* do not call grubby on ostree based distro

* update docs enabling containerd on fedora coreos

Update README for control_plane's external volume type variable

Clean up extra spaces, although these errors are not important, they affect the code specification.

* Ansible: move to Ansible 3.4.0 which uses ansible-base 2.10.10

* Docs: add a note about ansible upgrade post 2.9.x

* CI: ensure ansible is removed before ansible 3.x is installed to avoid pip failures

* Ansible: use newer ansible-lint

* Fix ansible-lint 5.0.11 found issues

* syntax issues
* risky-file-permissions
* var-naming
* role-name
* molecule tests

* Mitogen: use 0.3.0rc1 which adds support for ansible 2.10+

* Pin ansible-base to 2.10.11 to get package fix on RHEL8

* Fix ansible detection for python3 and ubuntu

* Fix oracle missing centos-extras repo for containerd/docker dependencies

Clean up extra spaces, although these errors are not important, they affect the code specification.

Clean up extra spaces, although these errors are not important, they affect the code specification.

* Update vars.md to remove mention of string syntax of node_labels

Fixes https://github.com/kubernetes-sigs/kubespray/issues/6215

* Try fix makrdown linting

* Update docs/vars.md

* Update nodes.md

* fix syntax

* fix syntax - part 2

* replace master with kube_control_plane

* return etcd-master

https://github.com/kubernetes-incubator/kubespray is an old link,
this updates the link.

* replaced deprecated python package with python3 package

* removed the version due to duplication

When reset, need to clean up directory /usr/libexec.

This replaces master with "control plane" in Kubespray docs
because of [1].

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

Although these errors are not important, they affect the code specification.

* Claico Docs: clarify the algorithm to calculate calico_veth_mtu

* Update sample calico_veth_mtu