Initial setup
https://popravak.wordpress.com/2014/07/31/initial-setup-of-palo-alto-networks-next-generation-firewall/
https://www.paloaltonetworks.com/documentation/61/pan-os/pan-os/getting-started/perform-initial-configuration.html
https://www.paloaltonetworks.com/documentation/61/pan-os/pan-os/getting-started/configure-interfaces-and-zones
https://www.paloaltonetworks.com/documentation/70/pan-os/pan-os/networking/configure-nat