During spring training last year, this column detailed a class-action suit filed by three ex-minor leaguers alleging Major League Baseball paid them less than fast-food workers. Unrepresented by a labor union, minor leaguers toil 50 to 70 hours per week through a five-month season for subminimum wage with no overtime and no compensation during spring training, instructional leagues or winter leagues. Minor leaguers must serve a minimum of seven seasons to gain eligibility for free agency. And the few ballplayers who …