The Medford Chess Club invites you to its weekly meet-up in Medford Square, being held this week at the Great American Beer Hall on Mystic Avenue due to the spring book and bake sale taking place at the library, the usual meeting site. The session also will occur three hours earlier than usual, from 10 a.m. to noon. The club has chess sets, chess clocks, and helpful members to teach you the rules if you're new to the game. Players…