NEW YORK (Reuters) - A gauge of stocks across the world rose on Monday, led by a rebound on Wall Street, even as rising COVID-19 cases threaten to stall the recovery of the world's largest economy.Contracts to buy U.S. previously owned homes rose by the highest percentage on record in May. But they remained below their February level and were down compared with May 2019, which also kept alive expectations for even more economic stimulus."The market believes that the (Federal Reserve) has its..