NEW YORK — The Rhythm Nation will get “hot in herre” this summer as Janet Jackson has announced new summer dates of her Together Again tour, with rapper Nelly opening all shows. The five-time Grammy Award winner has extended her highest-selling concert tour with a 35-date jaunt across the United States, kicking off June 4 in Palm Desert, California. The tour then makes stops in cities including Los Angeles, Denver, Chicago, Philadelphia, Hartford, Connecticut, and Buffalo, before making its way to the New York City area. Jackson’s Together Again tour will hit Newark’s Prudential Center on July…