eggert/tz — pull request #9 by benelog (2014-10-29 22:17:29+00:00)
Title: Correct DST in Asia/Seoul

Hello,

According to the Korean Wikipedia ( http://ko.wikipedia.org/wiki/%ED%95%9C%EA%B5%AD_%ED%91%9C%EC%A4%80%EC%8B%9C) , DST in Republic of Korean was as follows.

- 1948.06.01. 00:00 ~ 1948.09.13. 00:00
- 1949.04.03. 00:00 ~ 1949.09.11. 00:00
- 1950.04.01. 00:00 ~ 1950.09.10. 00:00
- 1951.05.06. 00:00 ~ 1951.09.09. 00:00
- 1955.05.05. 00:00 ~ 1955.09.09. 00:00
- 1956.05.20. 00:00 ~ 1956.09.30. 00:00
- 1957.05.05. 00:00 ~ 1957.09.22. 00:00
- 1958.05.04. 00:00 ~ 1958.09.21. 00:00
- 1959.05.03. 00:00 ~ 1959.09.20. 00:00
- 1960.05.01. 00:00 ~ 1960.09.18. 00:00
- 1987.05.10. 02:00 ~ 1987.10.11. 03:00
- 1988.05.08. 02:00 ~ 1988.10.09. 03:00

It almostly corresponds with the exsiting comments in 'asia' file.

# From Annie I. Bang (2006-07-10):
# http://www.koreaherald.co.kr/SITE/data/html_dir/2006/07/10/200607100012.asp
# The Ministry of Commerce, Industry and Energy has already
# commissioned a research project [to reintroduce DST] and has said
# the system may begin as early as 2008.... Korea ran a daylight
# saving program from 1949-61 but stopped it during the 1950-53 Korean War.

And I checked old newspapers in Korean, all articles correspond with data in Wikipedia.
For example, [the article in 1948](http://newslibrary.naver.com/viewer/index.nhn?articleId=1948060100209202008&editNo=1&printCount=1&publishDate=1948-06-01&officeId=00020&pageNo=2&printNo=7607&publishType=00020)(Korean Language) proved that DST started at June 1 in that year.
For another example, [the article in 1988](http://newslibrary.naver.com/viewer/index.nhn?articleId=1988050700099215012&editNo=1&printCount=1&publishDate=1988-05-07&officeId=00009&pageNo=15&printNo=6822&publishType=00020) said that DST started at 2:00 AM in that year.

I tried to find simple rules to define DST, like 'SUN=>1', but cannot make it except 1957-1960.