Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Update ipfilter 4.1.28 --> 5.1.2.

Approved by: glebius (mentor)
BSD Licensed by: Darren Reed <darrenr@reed.wattle.id.au> (author)

This commit was generated by cvs2svn to compensate for changes in r170263,
which included commits to RCS files with non-trunk default branches.

Import IPFilter 4.1.23 to vendor branch.
See src/contrib/ipfilter/HISTORY for details of changes since 4.1.13

Import IP Filter version 4.1.10

import ipfilter 4.1.8 into the kernel source tree