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/

General further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 3-Clause license.

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.

Renumber copyright clause 4

Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by: Jan Schaumann <jschauma@stevens.edu>
Pull Request: https://github.com/freebsd/freebsd/pull/96

Remove the advertising clause from UCB copyrighted files in usr.bin. This
is in accordance with the information provided at
ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change

Also add $FreeBSD$ to a few files to keep svn happy.

Discussed with: imp, rwatson

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.

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

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

If we can't change the scheduling priority, warn but still execute
the requested utility. This is how nice(1) traditionall behaved,
and the behaviour required by SUSv3 and POSIX.2 UPE.

Submitted by: Peter Avalos <pavalos@theshell.com> (partially)
Reviewed by: mike

Support the SUSv3 -n option and the "--" end of options marker.
Replace "command" with "utility" in the manual page & source to be more
consistent with the terminology used in the standard, and to hint that
shell builtin commands won't work.

Submitted by: Peter Avalos <pavalos@theshell.com> (partially)
Approved by: mike

According to POSIX, exit status must be 127 if the requested utility was not
found, 126 if the execvp() failed for any other reason.

Similar to rev. 1.6 to src/usr.bin/env/env.c

Reviewed by: mike

remove __P

Style improvements recommended by Bruce as a follow up to some
of the recent WARNS commits. The idea is:

1) FreeBSD id tags should follow vendor tags.
2) Vendor tags should not be compiled (though copyrights probably should).
3) There should be no blank line between including cdefs and __FBSDIF.

Warns cleanup. Add FreeBSD ID to Makefile and nice.c.

Clean up some ambiguous nested if/elses.

Finish importing Lite2's src/usr.bin, except for ex, diff, grep, mail,
pascal and vmstat.sparc. All changed files on the vendor branch should
already have been imported.

remove duplicated usage string from commit rev 1.2
fix usage()

Check the # of arguments, instead of silently dumping core.

BSD 4.4 Lite Usr.bin Sources