Harry Shearer  With the Mississippi River about to overflow its banks in the beleaguered city of New Orleans, the specter of Hurricane Katrina, a devastation the city has still not recovered from, becomes an interesting focus of renewed speculation from a somewhat unlikely source. Harry Shearer, the Saturday Night Live veteran, actor/director of several “mockumentaries” (SPINAL TAP) and the voice of several characters on THE SIMPSONS, who also is a New Orleans residen...