A lawsuit accusing the National Hockey League of encouraging violence on the ice while misrepresenting the danger posed by repeated head trauma belongs in state court, a federal judge held.In a written opinion, U.S. District Judge Thomas M. Durkin of the Northern District of Illinois remanded to Cook County Circuit Court a suit filed on behalf of Steven R. Montador’s estate against the National Hockey League and its board of governors.Durkin rejected the NHL’s argument that Section 301 of the federal Labor …