pfSense

Avoid reseting firewall hostname by WAN DHCP. It should fix #3746

Fix #3700 and other syntax issues:

- Remove G parameter from pfctl since it doesn't exist anymore
Initialize $old_router
- Fix sh syntax on variable assign, it couldn't have space before =
- Simplify logic
- Avoid flush states twice, if it was done on IP change, don't do it...

Remove unused ppp-script

Whitespace fixes

Set the interface as first here to properly be able to identify it after in php code. Ticket #2495

Tune up a bit dhclient-script and call the kill state command only once its enough

Ticket #1629 Another round of fixes related to state clearing

Use the better -Fs modifies to pf to kill the states by interface. Also kill both sides on an interface when -k needs to be used

pfctl -b is gone just use std tools of pfctl

The ISC client was far worse then the WIDE client was, back to plan A
Revert "Merge changes required for using the ISC dhclient in pfSense with prefix delegation. This should hopefully be a bit more reliable in the long run."

This reverts commit 651018775c78e38045966825b920b641a0302b43....