pfSense

Fix #3079, add a section for DHCPv6 Server backup

Implement URL Table aliases for ports instead of IP addresses

fix description

touch up text

Add support for protocol 41 in rules. Fixes #3007.

Make dashboard update check respect nanobsd-vga, probably fixes #3078

Correct month, quarter (3 months), and 4 year RRD graphs length.

Longest possible month is 31 days, not 32.
Longest possible quarter (3 months) is 92 days (30+31+31), not 93 (31+31+31).
4 Years is 1461 days (365 x 4 + 1), not 1464 (366 x 4). Except about once every century or so when leap year is skipped 4 years is then 1460 days. But that is not going to happen again for a very long time. Unfortunately pfSense, nor anyone alive today will probably still be alive by then.

Remove unecessary variable

Fix #2962, allow to remove VIP if gateway IP is on the interface's subnet

fix typo