- name: Restart apache2
  service:
    name: apache2
    state: restarted

- name: Restart apache2
  service:
    name: apache2
    state: restarted
  register: apache_restart
  until: apache_restart|success
  retries: 5
  delay: 2

Add retry to restart of apache2
Add retry to restart of apache2

This commit adds a retry to the restart of apache2 in the
horizon_extensions role.  This is will hopefully fix the periodic
restart failures that we see in the gate that appear to be
environmental (ie. a result of the instance's load).

We have attempted to debug a misconfiguration of port, another service
binding to ports 80/443, but in both situation everything appeared as
expected.  Also, we attempted to recreate this in a development
environment but were not able to replicate teh failure.

Connects https://github.com/rcbops/u-suk-dev/issues/552
