WASHINGTON Well, at least one part of the White House is heeding calls for new blood. Not only is the pastry chef quitting this week, a close look at the first lady's office shows that she has replaced her entire high command after five years in charge of the East Wing. Laura Bush is now on her second chief of staff, Anita McBride. She is on her second projects and policy director, Sonya Medina. She is on her third press secretary, Susan Whitson. She is on her second social secretary, Lea Berman. On the residence staff, she is on her...