roles/common: Remove Ubuntu 14.04 logic

We're only supporting Ubuntu 16.04 now.

roles/common/tasks/firewall_Ubuntu.yml

@@ -1,21 +1,4 @@
 ---
-- name: Install iptables-persistent
-  when: ansible_distribution_version | version_compare('14.04', '==')
-  apt: pkg=iptables-persistent update_cache=yes
-  tags: packages
-
-- name: Copy /etc/iptables/rules.v4
-  when: ansible_distribution_version | version_compare('14.04', '==')
-  template: src=iptables.j2 dest=/etc/iptables/rules.v4 owner=root mode=0600
-  notify:
-    - restart iptables-persistent
-
-- name: Copy /etc/iptables/rules.v6
-  when: ansible_distribution_version | version_compare('14.04', '==')
-  template: src=ip6tables.j2 dest=/etc/iptables/rules.v6 owner=root group=root mode=0600
-  notify:
-    - restart iptables-persistent
-
 - name: Install firewalld and deps
   when: ansible_distribution_version | version_compare('15.04', '>=')
   apt: pkg={{ item }} state=latest