CBS News fired a senior employee on Tuesday for violating the sacred journalistic principles of "trust and mutual respect." Scott Pelley, 68, got the axe after a preening confrontation with 60 Minutes executive producer Nick Bilton in which Pelley disparaged his supervisor with "remarkable incivility and contempt." Pelley, best known as one of the deep-voiced commentators who helps America's senior citizens fall asleep after football games, lashed out in response. He issued an intolerably long