GLOBAL MARKETS-Stocks & bonds rally, dollar dips as Summers quits Fed race

* Dollar falls as Summers drops out of running for Fed chair * Summers was seen as more hawkish than Yellen * Shares, bonds rally on view policy to stay easy for longer * U.S. stocks advance, though Apple limits Nasdaq's rally By Ryan Vlastelica NEW YORK, Sept 16 (Reuters) - U.S. stocks and Treasuries rallied on Monday as investors saw the withdrawal of Lawrence Summers from the running to head the Federal Reserve as making a more gradual approach to monetary tightening mor