pf: convert DIOCGETSTATUS to netlink

Introduce pfctl_get_status_h() because we need the pfctl_handle. In this variant
use netlink to obtain the information.

Sponsored by: Rubicon Communications, LLC ("Netgate")

libpfctl: allow access to the fd

pfctl_open() opens both /dev/pf and a netlink socket. Allow access to the /dev/
pf fd via pfctl_fd().
This means that libpfctl users no longer have to open /dev/pf themselves for any
calls that are not yet available in libpfctl.

Sponsored by: Rubicon Communications, LLC ("Netgate")
MFC after: 2 weeks

libpfctl: introduce a handle-enabled variant of pfctl_add_rule()

Introduce pfctl_add_rule_h(), which takes a pfctl_handle rather than a
file descriptor (which it didn't use). This means that library users can
open the handle while they're running as root, but later drop privileges
and still add rules to pf.

Sponsored by: Rubicon Communications, LLC ("Netgate")

pf (t)ftp-proxy: use libpfctl instead of DIOCGETSTATUS

Prefer libpfctl functions over direct access to the ioctl whenever
possible. This will allow subsequent removal of DIOCGETSTATUS (in 15) as
there already is an nvlist-based alternative.

MFC after: 1 week
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D41647

ftp-proxy: Revert incorrect migration to libpfctl

libpfctl supports creating rules, but not (yet) adding addresses to a
pool. Adding addresses certainly does not work through adding a rule.

PR: 256917
MFC after: 1 week
Sponsored by: Rubicon Communications, LLC ("Netgate")

libpfctl: Switch to pfctl_rule

Stop using the kernel's struct pf_rule, switch to libpfctl's pfctl_rule.
Now that we use nvlists to communicate with the kernel these structures
can be fully decoupled.

Reviewed by: glebius
MFC after: 4 weeks
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D29644

(t)ftp-proxy: use libpfctl

Reviewed by: glebius
MFC after: 4 weeks
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D29641

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Create the altix project branch. The altix project will add support
for the SGI Altix 350 to FreeBSD/ia64. The hardware used for porting
is a two-module system, consisting of a base compute module and a
CPU expansion module. SGI's NUMAFlex architecture can be an excellent
platform to test CPU affinity and NUMA-aware features in FreeBSD.

- Import the HEAD csup code which is the basis for the cvsmode work.

Import pf userland from OpenBSD 4.1 and (for ftp-proxy) libevent 1.3b as
a local lib.