Add docker role for Linux.

ansible/roles/docker/tasks/common.yaml

@@ -0,0 +1,15 @@
+- import_tasks: tasks/freebsd.yaml
+  when: 'os_flavor == "freebsd"'
+
+- import_tasks: tasks/linux.yaml
+  when: 'os_flavor == "linux"'
+
+- include_tasks:
+    file: tasks/peruser.yaml
+    apply:
+      become: yes
+      become_user: "{{ initialize_user }}"
+  when: users is defined
+  loop: "{{ users | dict2items | community.general.json_query('[?value.initialize==`true`].key') }}"
+  loop_control:
+    loop_var: initialize_user