NEW YORK (Reuters) - Oil prices climbed on Thursday, with Brent rising above $61 a barrel as a surprise drop in U.S. crude inventories and the prospect of further market-supporting action by OPEC and its allies offset some concern over the outlook for demand.U.S. inventories dropped by 1.7 million barrels in the week to Oct. 18, and one analyst said stocks could fall further in coming weeks. OPEC and its allies meet in early December and could, officials have said, opt to deepen supply curbs...