Install docker

docker.yml

---
- hosts: all
  remote_user: antonio
  sudo: yes
  tasks:
    - name: ensure apt can deal with https
      apt: name=apt-transport-https state=present
    - name: add the docker repository
      apt_repository: repo='deb https://get.docker.io/ubuntu docker main' state=present
    - name: update the system
      apt: update_cache=yes upgrade=yes
    - name: install docker
      apt: name=lxc-docker state=latest