Trump White House press secretary Stephanie Grisham will speak at the Democratic National Convention this week, one of several Republican voices meant to highlight the “extremism” of Donald Trump. “I never thought I’d be speaking at a Democratic convention. But, after seeing firsthand who Donald Trump really is, and the threat he poses to our country, I feel very strongly about speaking out,” Grisham said in an exclusive statement to NBC News. Grisham was a press aide during Trump’s 2016...