Define and implement specs for bootstrap-os (#4455)

* 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

roles/bootstrap-os/tasks/bootstrap-coreos.yml

@@ -1,4 +1,6 @@
 ---
+# CoreOS ships without Python installed
+
 - name: Check if bootstrap is needed
   raw: stat /opt/bin/.bootstrapped
   register: need_bootstrap
@@ -16,39 +18,20 @@
 
 - name: Run bootstrap.sh
   script: bootstrap.sh
-  when: need_bootstrap.rc != 0
+  become: true
+  when:
+    - need_bootstrap.rc != 0
 
-- set_fact:
+- name: Set the ansible_python_interpreter fact
+  set_fact:
     ansible_python_interpreter: "{{ bin_dir }}/python"
   tags:
     - facts
 
-- name: Install pip3
-  command: "{{ ansible_python_interpreter }} -m ensurepip"
-  args:
-    creates: "{{ bin_dir }}/pypy3/bin/pip3"
-  register: pip_installed
-
-- name: Install pip3 link
-  file:
-    src: "{{ bin_dir }}/pypy3/bin/pip3"
-    dest: "{{ bin_dir }}/pip3"
-    mode: 0755
-    state: link
-  when: pip_installed.changed
-
-- name: Install required python modules
-  pip:
-    name: "{{ item }}"
-    extra_args: "{{ pip_extra_args | default(omit) }}"
-  with_items: "{{ pip_python_coreos_modules }}"
-  environment:
-    PATH: "{{ ansible_env.PATH }}:{{ bin_dir }}"
-
 - name: Disable auto-upgrade
   systemd:
     name: locksmithd.service
     masked: true
     state: stopped
   when:
-    - not coreos_auto_upgrade
+    - coreos_locksmithd_disable