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

[Paul Eggert]

Random832 wrote:
> I meant D as in the military name of UTC+04, not daylight.

Ah, sorry, I misunderstood.

Single-letter names are too short to conform to POSIX (which requires at least 3 
characters). Also, they are problematic on the net because Internet RFC 822 got 
them wrong (the sign was reversed). For this reason RFC 1123 says they "carry no 
information" in email Date: lines, and RFC 5322 says something similar. Also, 
single-letter names can't handle UTC offsets like +1400 and +0530 that are in 
practical use today. With all these problems I think we can safely exclude them 
from our bag of tricks.