Politico: The climate deal reached between U.S, China and other great powers on Friday night is so vague, hastily hatched and non-binding President Obama isn`t even sure he`ll be required to sign it. "You know, it raises an interesting question as to whether technically there’s actually a signature… It’s not a legally binding agreement, I don’t know what the protocols are,’ said a bleary-eyed Obama, before hopping in Air Force One for the trip back to Washington. Even as he left, it …