* Remove leftover files for Coreos

Coreos was replaced by flatcar in 058438a2 but the file was copied
instead of moved.

* Remove workarounds for resolved ansible issues

* boostrap: Use first_found to include per distro

Using directly ID and VARIANT_ID with first_found allow for less manual
includes.
Distro "families" are simply handled by symlinks.

* boostrap: don't set ansible_python_interpreter

- Allows users to override the chosen python_interpreter with group_vars
  easily (group_vars have lesser precedence than facts)
- Allows us to use vars at the task scope to use a virtual env

Ansible python discovery has improved, so those workarounds should not
be necessary anymore.
Special workaround for Flatcar, due to upstream ansible not willing to
support it.

no_proxy is a pain to get right, and having proxy variables present causes issues
(k8s components get proxy configuration after upgrade, see #7100)

It's better to only configure what require proxy:
- the runtime (containerd/docker/crio)
- the package manager + apt_key
- the download tasks

Tested with the following clusters
- 4 CentOS 8 nodes
- 1 Ubuntu 20.04 node

Signed-off-by: Etienne Champetier <champetier.etienne@gmail.com>

* Add support for http(s)_proxy to CoreOS and Fedora

* fix opensuse proxy support

* Fix CoreOS proxy support

* update documentation

* Add README to bootstrap-os role

* Rework bootstrap-os once more

* Document workarounds for bugs/deficiencies in Ansible modules
* Unify and document role variables
* Remove installation of additional packages and repositories
* Merge Ubuntu and Debian tasks
* Remove pipelining setting from default playbooks
* Fix OpenSUSE not running its required tasks

* bootstrap: rework role

* support being called from a non-root user
* run some commands in check mode
* unify spelling/task names

* bootstrap: fix wording of comments for check_mode: false

* bootstrap: remove setup-pipelining task

* Update the version of pypy used on CoreOS bootstrap-os

* update the pip installation process on CoreOS

* Disable locksmithd on CoreOS if coreos_auto_upgrade set to false

* change when format to support multiple-condition

pip was always being downloaded on subsequent runs, This PR always runs the pip command, and checks the rc of it before downloading pip

Fix in favor of #2582

* Change deprecated vagrant ansible flag 'sudo' to 'become'

* Emphasize, that the name of the pip_pyton_modules is only considered in coreos

* Remove useless unused variable

* Fix warning when jinja2 template-delimiters used in when statement

There is no need for jinja2 template-delimiters like {{ }} or {% %}
any more. They can just be omitted as described in https://github.com/ansible/ansible/issues/22397

* Fix broken link in getting-started guide

Also fix usage of failed_when and handling exit code.

* Adding yaml linter to ci check

* Minor linting fixes from yamllint

* Changing CI to install python pkgs from requirements.txt

- adding in a secondary requirements.txt for tests
- moving yamllint to tests requirements

Migrate older inline= syntax to pure yml syntax for module args as to be consistant with most of the rest of the tasks
Cleanup some spacing in various files
Rename some files named yaml to yml for consistancy

"shell" step doesn't support check mode, which currently leads to failures,
when Ansible is being run in check mode (because Ansible doesn't run command,
assuming that command might have effect, and no "rc" or "output" is registered).

Setting "check_mode: no" allows to run those "shell" commands in check mode
(which is safe, because those shell commands doesn't have side effects).

Signed-off-by: Bogdan Dobrelya <bogdando@mail.ru>

Add tags to allow more granular tasks filtering.
Add generator script for MD formatted tags found.
Add docs for tags how-to.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

A freshly-installed CoreOS system does not always have a hostname configured.
This causes problems for etcd and BGP mesh configuration for Calico.
Assign the Ansible inventory name as hostname as part of CoreOS bootstrap,
if the hostname is the default ("localhost").

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