support for Chess960 a.k.a. Fischer random chess

As of version 2.08, pgn4web supports the variant Chess960, a.k.a. Fischer random chess.

These are the last two games of the Chess960 rapid world championship 2006 in Mainz (Germany) between Levon Aronian (Armenia) and Peter Svidler (Russia). Aronian won the match 5-3, with no draws!

More info at the Chess960 page of the pgn4web wiki!