Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

flowctl: low-effort fix to make it compilable with neither inet nor inet6

Convert usr.sbin to LIBADD
Reduce overlinking

Use src.opts.mk in preference to bsd.own.mk except where we need stuff
from the latter.

Conditionally compile in the IPv4/IPv6 address family support.
Test it with feature_present(3), so that we do not end up with passing
an unsupported version to NgSendMsg(3).

Approved by: glebius

Rewrite the flowctl utility to add it support for displaying
both IPv4 and IPv4 flows.

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.

Man page for flowctl utility.

mdoc(7) lessons by: ru
Approved by: julian (mentor)

Userland control utility for ng_netflow.

Approved by: julian (mentor)