Clarify that the USSR no longer exists, but some of the holidays are
celebrated anyway.
Reviewed in part by: ru
Remove Jewish and most Muslim holidays. They're all wrong, since they
don't apply to the Western calendar. The much more complete Jewish
holidays are in calendar.judaic. The Muslim holidays need to be
collected into a file, but there's not much point in having the wrong
date.
Remove many Fiji holidays. They change every year by Government
decree, and some were duplicated as a result.
Remove some duplicates.
There's still a lot to be done; in particular, I think the Japanese
and British holidays are very inaccurate. This file needs checking by
people who know the details.
c398fe500e