Implement persistence of iptables on reboot

Use the iptables-persistent package
to implement persistence of iptables during a reboot
for Ubuntu and Debian.
Entries are saved to /etc/iptables/rules* on add-rule.
These entries are restored on reboot.
( Note in later versions iptables-persistent is replaced
by netfilter-persistent with plugins in iptables-persistent)

Change-Id: I44b625111d5db34a444c5aa4f6e31c6009c8a6f5
Merge "Implement persistence of iptables on reboot"