By Denny Dyroff, Entertainment Editor, The Times Motown the Musical The popularity of the “Motown Sound” has remained at a high level for more than 50 years. “Motown the Musical,” which celebrates Berry Gordy and his label Motown Records, made its Broadway debut in April 2013 on Broadway at the Lunt-Fontanne Theatre, and its popularity has remained at a high level for more than three years. “Motown...