Split deploy steps in separate playbooks: part1 (#3451)

* Fix bootstrap_os/ubuntu idempotency

* Update bastion role

* move container_engine in sub-roles

* requires ansible 2.5

* ubuntu18 as first CI job

roles/container-engine/docker/vars/ubuntu-bionic.yml

@@ -0,0 +1,31 @@
+---
+docker_kernel_min_version: '3.10'
+
+use_docker_engine: false
+
+docker_versioned_pkg:
+  'latest': docker-ce
+  '18.03': docker-ce=18.03.1~ce-3-0~ubuntu
+  '18.06': docker-ce=18.06.1~ce~3-0~ubuntu
+  'stable': docker-ce=18.06.1~ce~3-0~ubuntu
+  'edge': docker-ce=18.06.1~ce~3-0~ubuntu
+
+docker_package_info:
+  pkg_mgr: apt
+  pkgs:
+    - name: "{{ docker_versioned_pkg[docker_version | string] }}"
+      force: yes
+
+docker_repo_key_info:
+  pkg_key: apt_key
+  url: '{{ docker_ubuntu_repo_gpgkey }}'
+  repo_keys:
+    - 9DC858229FC7DD38854AE2D88D81803C0EBFCD88
+
+docker_repo_info:
+  pkg_repo: apt_repository
+  repos:
+    - >
+       deb [arch=amd64] {{ docker_ubuntu_repo_base_url }}
+       bionic
+       stable