Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

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

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Long awaited update to the calendar system:

- Repeating events which span multiple years (because of -A, -B or
just the three days before the end of the year).

- Support for lunar events (full moon, new moon) and solar events
(equinox and solstice, chinese new year). Because of this, the
options -U (UTC offset) and -l (longitude) are available to
compensate if reality doesn't match the calculated values.

MFC after: 1 month

DEBUG is either defined or not defined for the 'calender' sources, so use #ifdef and not just #if -- both to be semantically correct and also to be aligned with the rest of the 'calendar' sources

- Remove times.h from C programs that does not manipulate with time at
all.
- Remove pathnames.h from all but io.c since it's the only module that
used these definations.

Revert most part of 200420 as requested, as more review and polish is
needed.

Remove unneeded header includes from usr.bin/ except contributed code.

Tested with: make universe

style(9)ify usr.bin/calendar

PR: bin/118644
Approved by: bde@ (mentor)
MFC after: 1 week

ANSIfy function definitions.
Move some extern declarations to a header file.
Remove an unneeded extern declaration for optarg.

Style improvements recommended by Bruce as a follow up to some
of the recent WARNS commits. The idea is:

1) FreeBSD id tags should follow vendor tags.
2) Vendor tags should not be compiled (though copyrights probably should).
3) There should be no blank line between including cdefs and __FBSDIF.

WARNS=2 fixup (mostly. Some are Hard To Fix(tm), so NO_WERROR is set)
Use __FBSDID().
Sort some headers.

Use a slightly better documented way of calculating easter and
include a reference to the Calendar FAQ. Also make argument parsing
a little more robust.

PR: 23881

$Id$ -> $FreeBSD$

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.

sync copyright with /usr/share/examples/etc/bsd-style-copyright

Includes cleanup
Submitted by: bde

Allow to configure national Easter names.
Speedup my national months/days handling code.

Localize it
Handle Orthodox Eastern
-Wall cleanup

- handle events that move around from year to year, i.e.,
``the last Monday in April'
- handle easter

new options
-f calendarfile
-A days
-B days

Calendar HOME directory ~/.calendar
don't sent mail if ~/.calendar/nomail exist