Remove $FreeBSD$: one-line sh pattern

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

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

various: general adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

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.

No functional change intended.

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.

The original adduser/rmuser scripts in Perl used to modify the PATH
setting. When the scripts were converted to Bourne shell, this was
removed. The adduser script was changed to use an explicit path for
the pw(8) command so that /usr/sbin did not have to be in the user's
PATH. The rmuser script continued to assume that /usr/sbin was in the
user's path, however. This fixes the rmuser script to use an explicit
path for pw(8) similar to adduser.

MFC after: 2 weeks

The POP daemon's temporary mail file has a leading dot ('.'). This was
lost in the shell script rewrite of the rmuser command.

Submitted by: Ian Smith <smithi@nimnet.asn.au>

Fix a particularly egregious grammar error.

Approved by: wpaul
MFC after: 1 day

Make rmuser now also remove ipc resources. Also, fix a few minor
shell style problems (superfluous backslashes at EOL).

PR: 55980
Submitted by: Chris S.J.Peron <maneo@bsdpro.com>
MFC after: 2 weeks

Update my email address.

Update copyright.

Condense the output to one line per removed user. For user's who
want the more verbose version, there's a -v option.

Approved by: markm (mentor)

expr foo -> $((foo))

Do not loose trailing spaces when printing prompt messages.

Correctly handle files with IFS characters (spaces) in their names when
cleaning up temporary files.

Submitted by: Mike Makonnen <mtm@identd.net>
Approved by: re

Replace the perl versions of adduser and rmuser with shell script versions.

Submitted by: Mike Makonnen <mtm@identd.net>
Approved by: re