Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

More -Wmissing-variable-declarations fixes.

In addition to adding missing `static' keywords:
- bin/dd: Pull in `extern.h' to guarantee consistency with source file.
- libexec/rpc.rusersd: Move shared globals into an extern.h.
- libexec/talkd: Move `debug' and `hostname' into extern.h.
- usr.bin/cksum: Put counters in extern.h, as they are used by ckdist/mtree.
- usr.bin/m4: Move `end_result' into extern.h.
- usr.sbin/services_mkdb: Move shared globals into an extern.h.

Port all apps in libexec/ from libulog to utmpx.

Make WARNS=6 the default for libexec/.

Just like bin/ and sbin/, I think setting WARNS to the highest value
possible will make it more attractive for people to fix warnings.

- The WARNS variable is set in the Makefile in the directory of the
application itself, making it more likely that it will be removed out
of curiosity to see what happens.
- New applications will most likely build with WARNS=6 out of the box,
because the author would more likely fix the warnings during
development than lower WARNS.

Unfortunately almost all apps in libexec require a lowered value of
WARNS.

Make rpc.ruserd work with utmpx/libulog.

Because strings are now null-terminated, I've decided to just use an
array of utmpx structures, instead of the separated strings. This means
we just copy the entire utmpx structure and point to the strings within
the structures directly.

Perform cleanups to rpc.rusersd:

- Perform whitespace fixes. Use tabs instead of 8 spaces.
- Make it build at WARNS=6.

- Backout botched attempt to intoduce MANSECT feature.
- MAN[1-9] -> MAN.

Set the default manual section for libexec/ to 8.

$Id$ -> $FreeBSD$

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.

Correct the ancient paths here in case someone ever uncomments this again.

Comment out the XIDLE extension stuff, it breaks make world on systems
with Xinside's CDE installed

This commit was generated by cvs2svn to compensate for changes in r2337,
which included commits to RCS files with non-trunk default branches.

rusersd from FreeBSD 1.1.5.1
Reviewed by: geoff.
Submitted by: John Brezak