Fix service name for xenial and newer distributions using netfilter

iptables/map.jinja

 {% set service = salt['grains.filter_by']({
     'Debian': {
         'pkgs': ['iptables','iptables-persistent' ],
-        'service': 'iptables-persistent',
+        'service': 'netfilter-persistent',
     },
     'RedHat': {
         'pkgs': ['iptables'],
         'service': 'iptables',
     },
-}, merge=salt['pillar.get']('iptables:service')) %}
+}, merge=salt['grains.filter_by']({
+    'trusty': {
+        'service': 'iptables-persistent',
+    },
+}, grain='oscodename', merge=salt['pillar.get']('iptables:service'))) %}

iptables/service.sls

   - names: {{ service.pkgs }}
 
 iptables_services:
+{%- if grains.init == 'systemd' %}
+  service.running:
+{%- else %}
   service.dead:
+{%- endif %}
   - enable: true
   - name: {{ service.service }}
   - sig: test -e /etc/iptables/rules.v4