(REUTERS)  Christina Grimmie, a rising singing star who gained fame as a YouTube sensation and a contestant on television’s “The Voice,” was shot dead while signing autographs for fans after a concert in Orlando, police said on Saturday. Grimmie, 22, was greeting fans along with members of the band Before You Exit after a performance on Friday at the Plaza Live music venue when a gunman approached and opened fire shortly before 10:30 p.m., […]