Stacy Keach is off to Australia for the film “Truth” co-starring Cate Blanchett and Robert Redford. Directed by James Vanderbilt, Truth is based on Mary Mapes’ 2005 memoir Truth and Duty: The Press, the President, and the Privilege of Power. Truth centers on the firestorm and ensuing “Rathergate” scandal that erupted in September 2004 after Rather reported that George W. Bush had received special treatment while serving in the Air National Guard during the Vietnam War, a report that was based on some documents that were suspected to be forgeries.  Stacy plays Col. Bill Burkett, one of the whistle-blowers who pointed the finger at George W. Bush’s questionable military credentials