[tz] Astrakhan region got approval to change its time zone

[Paul Eggert]

Random832 wrote:
> How about "D"?

Under this proposal there is no "D" ("daylight") or "S" ("summer") in the 
abbreviation name. I view this as a feature, as often in these cases we are 
arbitrarily deciding whether the time is DST, and it's better to avoid inserting 
these inventions into tzdata when possible. We can't avoid this problem entirely 
(as tm_isdst needs *some* value) but the more we avoid making up stuff, the more 
reliable tzdata will be.