Remove copyright strings ifdef'd out

We've ifdef'd out the copyright strings for some time now. Go ahead and
remove the ifdefs. Plus whatever other detritis was left over from other
recent removals. These copyright strings are present in the comments and
are largely from CSRG's attempt at adding their copyright to every
binary file (which modern interpretations of the license doesn't
require).

Sponsored by: Netflix

usr.bin: 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 .c pattern

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

Mark usage function as __dead2 in programs where it does not return

In most cases, usage does not return, so mark them as __dead2. For the
cases where they do return, they have not been marked __dead2.

Reviewed by: imp
Pull Request: https://github.com/freebsd/freebsd-src/pull/735

spdx: initial adoption of licensing ID tags.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.

Initially, only tag files that use BSD 4-Clause "Original" license.

RelNotes: yes
Differential Revision: https://reviews.freebsd.org/D13133

Add missing static keywords to rwall(1)

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.

Revert most part of 200420 as requested, as more review and polish is
needed.

Remove unneeded header includes from usr.bin/ except contributed code.

Tested with: make universe

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

Sync program's usage() with manpage's SYNOPSIS.

More xdrproc_t warnings.

ANSIify function definitions.
Add some constness to avoid some warnings.
Remove use register keyword.
Deal with missing/unneeded extern/prototypes.
Some minor type changes/casts to avoid warnings.

Reviewed by: md5

Revert/fix the most controversial parts of the last commit:

1) place __FBSDID() correctly IAW style(9).

2) revert (and slightly correct) a "complex" expression in an if()
statement.

ANSIfication, WARNS and lint cleanup.

Cleanup this code a bit by attempting to sync it up with NetBSD and
with each other.

Reviewed by: markm, dwmalone

$Id$ -> $FreeBSD$

PR: bin/8680

Minor adjustments to rwall.c. Increased the size of a couple of char
arrays and replaced a potentially dangeerous strcpy/strcat with snprintf().

Use err(3). Add usage().

Revert $FreeBSD$ to $Id$

Make the long-awaited change from $Id$ to $FreeBSD$

This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.

Fix bug found by new prototypes. The code was passing an int to a function
that was expecting a "struct timeval" on the stack. I've guessed at a
suitable replacement timeout.

Remove trailing whitespace.

rwall from FreeBSD 1.1.5.1
Reviewed by: Geoff
Submitted by: Christopher G. Demetriou