Shutdown Docker before upgrading the rpm.

This avoids the automatic image migration in 1.10, which can take a very
long time and potentially cause rpm db corruption.

playbooks/common/openshift-cluster/upgrades/docker/upgrade.yml

@@ -18,9 +18,13 @@
   register: nuke_images_result
   when: docker_upgrade_nuke_images is defined and docker_upgrade_nuke_images | bool
 
+- service: name=docker state=stopped
+
 - name: Upgrade Docker
   action: "{{ ansible_pkg_mgr }} name=docker{{ '-' + docker_version }} state=present"
 
+- service: name=docker state=started
+
 - name: Restart containerized services
   service: name={{ item }} state=started
   with_items: