+2013-03-20 Daigo Moriwaki <daigo at debian dot org>
+
+ * [shogi-server]
+ - New pairing algorithm: ShogiServer::Pairing::LeastDiff
+ This pairing algorithm aims to minimize the total differences of
+ matching players' rates. It also includes penalyties when a match
+ is same as the previous one or a match is between human players.
+ It is based on a discussion with Yamashita-san on
+ http://www.sgtpepper.net/kaneko/diary/20120511.html.
+