pfSense

This is 2020. Issue #9245

Update copyright notices to 2019. Happy New Year

(cherry picked from commit 0b4c14a491664053aad3cc76e1ffd67b70ff2da1)

Update the Copyright notice for pfSense.

Move copyright from ESF to Netgate

Move to Apache License 2.0

Review license / copyright on all files (final round)

Always use require_once

The usage of require() and require_once() throughout the system is
inconsistent, and "bugs" come up now and then when the order of
"requires" is a bit different and some require() happens after the
include file is already included/required....

Calling all of these "Page" in the privilege name is redundant since they are all pages and the "WebCfg" prefix implies they are pages.

Copyright updates Batch 2 of 3

Move main pfSense content to src/