Improve PHP 8 compatibility

Summary:
Mainly array key issues, at several places keys were used
with the expectation it returns null if the key doesn't exist.

HTTP_HOST can contains only the host, without port.

Side edit: update fortunes path for FreeBSD 12+

Test Plan: Tested on https://tools51.nasqueron.org tool by tool

Reviewers: dereckson

Reviewed By: dereckson

Differential Revision: https://devcentral.nasqueron.org/D2483