pfSense

Fix #6828

Until 2.3.x pfSense carried a patch that changed the behavior of 'route
change' command, making it add the route when it fails to change.
On 2.4 this patch was removed and will not be added back. This change
adjust PHP code to deal with route add / change and make it work...

Move copyright from ESF to Netgate

Move to Apache License 2.0

Review license / copyright on all files (1st round)

Check $active

Fix missing check for $active to avoid creating a route to a released lease.

Fix substr mistake

Made a silly mistake and overlooked an important difference between javascript substring() and php substr().
Tightened regex check for octal value.

Bugfixes & handling $duid and $type, Fixes #4206

This patch addresses:
1. Handling of IA_NA and IA_PD strings (that contain IAID+DUID content) using only the DUID part.
2. Fixing regular expression matching with respect to the IAID+DUID string regarding the legal \" substring (used in ISC DHCPv6 leases)....

Move main pfSense content to src/