Tweaks to make install run idempotent

roles/horizon/tasks/main.yml

@@ -1,8 +1,11 @@
 # Run hpc/horizon
 ---
+- set_fact:
+    docker_image: webhost12.service.rug.nl/hpc/openstack-horizon:latest
+
 - name: pull docker image
   docker_image:
-  name: webhost12.service.rug.nl/hpc/openstack-horizon:latest
+    name: "{{ docker_image }}"
   tags: pull
 
 - name: install service file.

roles/horizon/templates/horizon.service

@@ -12,8 +12,9 @@ ExecStart=/usr/bin/docker run --name %n \
   -e "KEYSTONE_HOST={{ hostvars[groups['keystone'][0]]['ansible_default_ipv4']['address'] }}" \
   --add-host=nova-controller:{{ hostvars[groups['nova-controller'][0]]['ansible_default_ipv4']['address'] }} \
   --add-host=keystone:{{ hostvars[groups['keystone'][0]]['ansible_default_ipv4']['address'] }} \
+  --add-host=neutron-controller:{{ hostvars[groups['neutron-controller'][0]]['ansible_default_ipv4']['address'] }} \
   -p 80:80 \
-  hpc/openstack-horizon
+  {{ docker_image }}
 
 [Install]
 WantedBy=multi-user.target