PLURAL-Support added

I have added the PLURAL support to Wikimedia SVN.

For translator: The PLURAL support is similar to the MediaWiki one. It support the language-specified forms with more / less than two froms. To use PLURAL you call (like in MediaWiki)

For developers: To use PLURAL in your messages, please use the "parsemag" option of msg() (for support use the value TRUE, default value is FALSE).

Jan Luca08:38, 5 July 2011