pfSense

3rd try!
- incorporate suggestions from @rbgarga with slight modification

(cherry picked from commit 6c2f093000b05285546e81dd1a578fc9b573b72b)

2nd try. . .

/etc/inc/util.inc:
- arp_get_mac_by_ip() updated to support IPv6
- attempt at code streamline

/usr/local/www/services_dhcp_edit.php:
- streamline code, now just a simple call to arp_get_mac_by_ip()

(cherry picked from commit dd83f869b79a858bd74c7a8bb4adcd49217445b0)

enhancements to services_dhcp_edit.php
- added ndp call to get MAC addr if remote client is connected via IPv6
- automatically hide `Copy MAC` button if arp/ndp returns null
- switch to exec() instead of backticks for calls to arp
- uses builtin is_ipaddr() function from util.inc...

Sync up status.php with master, but keep the 2.3/10.3-specific parts. Fixes #7246

Do not output PHP shell starup message unless it is run interactively. Fixes #7045

Fix for bug 6966 https://redmine.pfsense.org/issues/6966

Change-Id: I9471c2bbd8941e70965a86d369c8de87be9a4417
(cherry picked from commit 109a304e154a179bd340b06880ce95baec4dab03)

Revert "Fixed #6753"
User feedback suggests the sorted menu was better, despite the lack of consistency elsewhere.
This reverts commit 96ff627ff95e0fcadf8c15dbd6fe681309cb0fd8.

Mark missing parameter as required. It got lost during backport from master as spotted by @phil-davis

Required fields - Alias Type

should be a required field. And this 1-char change can also be backported to RELENG_2_3. I noticed this while looking at GUI pages in 2.3.3
(cherry picked from commit 8ea10c11441b5aed0b10eb14038aa8f8adbfb3de)

Fix #7157

trafficgraph: Don't update the on screen visual graph while invisible,
which avoids creating a large queue of pending timer objects waiting
for the next requestAnimationFrame to happen.

Submitted by: PiBa-NL at https://github.com/pfsense/pfsense/pull/3450