Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\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.

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

Use __unused macro instead of a bare void for main().

Suggested by: nectar

nologin(8) does not seem to require any command line parameters,
so remove argc and argv from main() argument.

At the same time, user and tt is not likely to be changed during
execution so mark them const.

This commit should guarantee nologin to pass WARNS=6.

Tested on: i386
MFC After: 1 month

Add standard copyright notice; fix style bugs. (Reported by bde)
Remove NO_NOLOGIN_LOG option now that we're off the root partition.

Report login attempts to syslog. Due to the statically-linked nature of
nologin(8), this causes a considerable (100K) increase in the binary size,
so I've added a NO_LOGIN_LOG option which disables this.

While I'm here, s/sizeof(MESSAGE)/sizeof(MESSAGE) - 1/, in order to
avoid writing the string-terminating zero byte.

No complaints from: -current
Approved by: rwatson (mentor)

Reimplement nologin(8) as a C program. This allows us to statically
link it at low cost and avoid environment poisoning attacks associated
with LD_LIBRARY_PATH.

Suggested by: rwatson