vor Tondro for The New York Times Barry and Fran Weissler's success as the pro=ucers of the musical "Chicago" enabled them to commission the artis= Beverly Pepper to build an amphitheater at their Westchester home. By GERALDINE F=BRIKANT chttp://topics.nytimes.com/top/referen=e/timestopics/people/f/geraldine_