Remove $FreeBSD$: one-line sh pattern

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

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.

The last big commit: let usr.sbin/ use WARNS=6 by default.

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

WARNS=6 cleanup. This includes:
- Apply __unused on unused parameters
- Use const where suitable
- Use PRIu64 instead of the deprecated %q
- Bump WARNS to 6

Perform a major cleanup of the usr.sbin Makefiles.
These are not perfectly in agreement with each other style-wise, but they
are orders of orders of magnitude more consistent style-wise than before.

- Backout botched attempt to introduce MANSECT feature.
- MAN[1-9] -> MAN.

Set the default manual section for usr.sbin/ to 8.

Add and activate the man page for memcontrol(8).

Reviewed by: msmith

Commandline tool for manipulating memory range attributes.