[tz] posix for asia/tehran is wrong

Mark tz at diramu.net
Fri Nov 30 00:20:45 UTC 2018

I've been adding DST time zone to espurna 

All dst entries but asia/tehran, use Mm.n.d format to specify dst dates.

The Tehran use 'Jn': "Asia/Tehran","<+0330>-3:30<+0430>,J80/0,J264/0"

When I implement this 'J' format, I came out a day short.

 From https://en.wikipedia.org/wiki/Iran_Standard_Time:

    The Iranian DST starts on March 22 and ends on September 22 each
    year with the exception of leapyears in which the DST starts and
    ends one day prior.

    Year 	DST Start Date and Time 	DST End Date and Time
    *2014* 	Sat, Mar 22, 0:00 AM 	Mon, Sep 22, 0:00 AM
    *2015* 	Sun, Mar 22, 0:00 AM 	Tue, Sep 22, 0:00 AM
    *2016* 	Mon, Mar 21, 0:00 AM 	Wed, Sep 21, 0:00 AM
    *2017* 	Wed, Mar 22, 0:00 AM 	Fri, Sep 22, 0:00 AM
    *2018* 	Thu, Mar 22, 0:00 AM 	Sat, Sep 22, 0:00 AM

This mean Tehran should be 
"Asia/Tehran","<+0330>-3:30<+0430>,80/0,264/0". The 'n' format, which 
counts 29 Feb, and starts count from 0, so would not come up a day short 
on non-leap years.

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