Singer-songwriter Jimmy Buffett, who popularized beach bum soft rock with the escapist Caribbean-flavored song “Margaritaville” and turned that celebration of loafing into an empire of restaurants, resorts and frozen concoctions, has died. He was 76.  The statement did not say where Buffett died or give a cause of death. Illness had forced him to reschedule concerts in May and Buffett acknowledged in social media posts that he had been hospitalized, but provided no specifics. “Margaritaville,” released on Feb. 14, 1977, quickly took on a life of its own, becoming a state of  mind for those ”wastin’ away,” an excuse for a life of low-key fun and escapism for those “growing older, but not up.”