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spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD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

my copyright: some minor adjustments

- remove "all rights reserved" from my copyright on my extensive
contributions
- belatedly add my name to tuning.7 which I was a large contributor to
several years ago

This commit can also serve as implicit permission for any formatting or
non-substantive changes that FreeBSD wishes to make in the future.

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.

ssh-copy-id: Add missing line continuation

PR: 194301
Reported by: pkubaj@riseup.net
Patch by: Ross Kilgariff <rosskilgariff@gmail.com>

Fix syntax error with modern shells

Submitted by: multiple

ssh-copy-id: add restorecon call

In certain situations when creating an authorized_key file on a Linux machine
restorecon(1) may need to be called. Therefore, attempt to run it if it exists.

MFC After: 1 week
Idea from: https://bugzilla.redhat.com/show_bug.cgi?id=739989

ssh-copy-id: avoid sending private keys; add -v option

To help avoid confusion: when attempting to send a key file check to see if a
file of the same name exists with a '.pub' suffix and send that instead. This
mimics the behavior of other ssh-copy-id scripts.

Add -v passthrough.

Reported by: dweimer <dweimer@dweimer.net>
Reported by: feld
MFC After: 1 week

Be a bit more paranoid.
Use more portable constructs in order to allow upstream adoption
Add per-file error messages

Reviewed by: jilles
Approved by: cperciva
MFC after: 1 week

Add a clean-room reimplementation of a script originally
found in openssh's contrib directory.

This version has more features and is better written.
I intend to submit this upstream as well.

Reviewed by: bapt
Reviewed by: des
Approved by: cperciva
MFC after: 1 week