 His name is Larry and his address is 10 Downing in London. That's the official residence and the office of the Prime Minister of the United Kingdom. You see, after one night of sweeping change last week across British politics, the one living and breathing fixture is Larry, the Downing Street cat. The white and tabby cat who bears the official title of Chief Mailster to the Cabinet Office was seen on the afternoon of July 5th hanging around the famous high gloss black door building.