rescue,nextboot: Install nextboot as a link to reboot, rm nextboot.sh

Reboot now emulates the nextboot shell script completely. Retire the
nextboot.sh script and install the link. Retain the same manual page,
since there's enough differences between nextboot and reboot that
talking about nextboot would likely be confusing in nextboot.8

The nextboot.sh script no longer exists, so doesn't need to be fixed up
to create rescue. However, now we need a link from nextboot to reboot.

Sponsored by: Netflix
Reviewed by: kevans
Differential Revision: https://reviews.freebsd.org/D43831
Differential Revision: https://reviews.freebsd.org/D43843

sbin: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl script.

Sponsored by: Netflix

Remove $FreeBSD$: one-line sh pattern

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

Explicitly add more files to the 'runtime' package.

Sponsored by: The FreeBSD Foundation

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.

Port the remaining apps in sbin/ to utmpx; only reboot(8).

Let init(8) and reboot(8) use utmpx to log wtmp entries.

logwtmp() gets called with the raw strings that are written to disk. For
regular user entries, this isn't too bad, but when booting/shutting
down, the contents get rather cryptic.

Just call the standardized pututxline().

Switch the default WARNS level for sbin/ to 6.

Submitted by: Ulrich Spörlein

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

Do not install boot_i386.8 on all architectures.

The kernel specified in main() of reboot(8) will be initialized
with -k option and never be used without kflag. This confuses
gcc because we set "kflag" at the same time with "kernel", but
the logic is not that apparant for gcc.

Since we can initialize "kernel" to NULL then know if "k" option
is set through determining whether it is still NULL, don't try
to have gcc to guess why we are connecting "kflag" with "kernel"
and use "kernel" directly in place of kflag.

Bump WARNS?= from 2 to 6

Share the i386 boot manual page.

Hook the new nextboot(8) manpage up to the build.

Add a nextboot script to make it easier to control the loader nextboot
support. Also, hook it up to the build.

Approved by: jake (mentor)

Default to WARNS=2.
Binary builds that cannot handle this must explicitly set WARNS=0.

Reviewed by: mike

Use ${MACHINE}, it works with cross-builds.

Constify and set WARNS=2.

Submitted by: Mike Barcroft <mike@q9media.com>

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

Removed the boot_*(8) man pages for machines we don't support:
hp300, sparc, tahoe, and vax

Totally revamp the man page, update to the state of affairs.

Make a link from boot_${ARCH}.8 to boot.8, so people will get what
they expect when asking "man boot".

I think David will lynch me when i'm requesting this to go into 2.1... :-)

Install aliases "fasthalt" and "fastboot" for halt and boot respectively.
This is for "backwards compatibility". Documented these aliases in the
manual page.

Convert to our man installation style. Also fixed long-standing bug
in `fastboot'/`fasthalt' in which the interpreter would hang around
after `reboot' or `halt' is run, causing an irritating ``Killed'' message.

Disable afterinstall: for manual pages until the manual page fix patch
comes in.

BSD 4.4 Lite sbin Sources

Note: XNSrouted and routed NOT imported here, they shall be imported with
usr.sbin.