Added Amazon Linux 2 support for deploying with docker (#5301)

roles/container-engine/docker/vars/amazon.yml

+---
+docker_kernel_min_version: '0'
+
+# https://docs.aws.amazon.com/en_us/AmazonECS/latest/developerguide/docker-basics.html
+
+docker_versioned_pkg:
+  'latest': docker
+  '18.03': docker-18.03.1ce-5.amzn2
+  '18.06': docker-18.06.1ce-10.amzn2
+
+docker_version: "latest"
+
+docker_package_info:
+  pkg_mgr: yum
+  pkgs:
+    - name: "{{ docker_versioned_pkg[docker_version | string] }}"

roles/kubernetes/preinstall/tasks/0080-system-configurations.yml

@@ -3,7 +3,9 @@
 - name: Confirm selinux deployed
   stat:
     path: /etc/selinux/config
-  when: ansible_os_family == "RedHat"
+  when:
+    - ansible_os_family == "RedHat"
+    - "'Amazon' not in ansible_distribution"
   register: slc
 
 - name: Set selinux policy
@@ -12,6 +14,7 @@
     state: "{{ preinstall_selinux_state }}"
   when:
     - ansible_os_family == "RedHat"
+    - "'Amazon' not in ansible_distribution"
     - slc.stat.exists
   changed_when: False
   tags: