MFC r313069:

Allow 999.local to run scripts in any language

If one of the scripts listed in (daily|weekly|monthly)_local is executable,
999.local should simply execute it. Only if the script isn't executable
should 999.local assume it needs /bin/sh.

Reviewed by: brian
MFC after: 3 weeks
Sponsored by: Spectra Logic Corp

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

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

Small adjustment to whitespace in output

Another overhaul of the periodic stuff.

All periodic sub-scripts <larf> now have their return codes interpreted
by periodic(8). Output may be masked based on variable values in
periodic.conf.

It's also now possible to email periodic output to arbitrary addresses,
or to send it to a log file, examples of which can be found in
newsyslog.conf.

The upshot of it all should be no discernable changes to the default
behaviour of periodic(8).

PR: 21250

Introduce /etc/defaults/periodic.conf, similar in concept to rc.conf.
The only change in the default functionality should be that
the output reports are slightly more verbose WRT files deleted.

Not objected to by: freebsd-arch

$Id$ -> $FreeBSD$

This commit was generated by cvs2svn to compensate for changes in r28263,
which included commits to RCS files with non-trunk default branches.

Copy /etc/cron.d to /etc/periodic per-request of many.
This wasn't done with a repository copy because there was no
history of any consequence. Flames to me.