Born September 19, 1920, steeped in the family business and sports, he is a national treasure.  The family business is The New Yorker, and the sport is, of course, baseball. His parents were Katherine Angell White, the accomplished longtime fiction editor of The New Yorker and Earnest Angell, a lawyer and one-time head of the American Civil Liberties Union.  So he comes by accomplishment naturally.  But step-father E.B. White is the name that is famous, so Angell's close connection to E.B. White is how many people know him. Roger Angell is 93 and still writing.  This Old Man appears in…