Fix broken unicode.org link

[Krinkle]

According to Internet Archive, the page used to look as follows: https://web.archive.org/web/20160229174411/http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html

The current page with that content seems to be http://cldr.unicode.org/index/cldr-spec/plural-rules.

[santhoshtr]

http://www.unicode.org/cldr/charts/latest/supplemental/language_plural_rules.html is the right one that match with http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html