Remove $FreeBSD$: one-line nroff pattern

Remove /^\.\\"\s*\$FreeBSD\$$\n/

libmd / md5: Add SHA-512/224.

While there, remove .Tn from man pages.

Also remove an obsolete comment about the 80386.

MFC after: 1 week
Sponsored by: Klara, Inc.
Reviewed by: kevans, allanjude
Differential Revision: https://reviews.freebsd.org/D38373

Fix wrong section number in man page cross references.

Fix a few mandoc issues

- skipping paragraph macro: Pp after Sh
- sections out of conventional order: Sh EXAMPLES
- whitespace at end of input line
- normalizing date format

Add missing errors section to md[2-5], ripemd160, sha*, and skein* manpages

PR: 148987
Submitted by: Dan Lukes <dan@obluda.cz> (original version)
MFC after: 1 week
Sponsored by: Klara Systems
Event: Waterloo Hackathon 2019

libmd: Always erase context in _Final method, and when doing
it, consistently use explicit_bzero().

Update manual pages to match the behavior.

Reviewed by: pfg, allanjude, jmg
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D16316

Integrate SHA2-224 with userspace components

The double compilation of the kernel sources in libmd and libcrypt is
baffling, but add yet another define hack to prevent duplicate symbols.

Add documentation and SHA2-224 test cases to libmd.

Integrate with the md5(1) command, document, and add more test cases;
self-tests pass.

Dereference nonexistent md2(3) manual.

MFC after: 3 days
Sponsored by: The FreeBSD Foundation

Rewrite HISTORY: The SHA256 code first appeared in 6.0, and the SHA512
code in 9.0; neither existed in FreeBSD 4.0.

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.

-mdoc sweep.

Correct type.

OK'ed by: cperciva

Removed redundnt empty line.

Approved by: re (blanket)

In light of the recent 2^69 operation collision-finding attack on SHA1,
add support for SHA256.

Tested on: i386, sparc64
Tested using: NIST test vectors, built-in tests
X-MFC-after: 5.4-RELEASE