NEW YORK -- Former New Jersey Gov. Chris Christie, a candidate for the Republican nomination for president, has a book coming out next year on the legacy of a GOP hero — former President Ronald Reagan. Threshold Editions, a conservative imprint at Simon & Schuster, announced Tuesday that it will publish “What Would Reagan Do?: Life Lessons from the Last Great President" on Feb. 6. “It's amazing what how much Reagan was able to achieve by sticking to his principles and connecting on a human level with those around him,” Christie writes in the introduction. “Each chapter of this book...