GLOBAL MARKETS-Shares slip on worries over Greece; oil drops

* U.S., European shares slip amid Greek debt meetings * Oil slips on record-high U.S. crude inventories * Gold hits one-month low (Updates market activity, prices) By Sam Forgione NEW YORK, Feb 11 (Reuters) - Stock markets worldwide slipped on Wednesday on investor worries over the outcome of euro zone ministerial meetings about Greece's debt crisis, while oil prices dropped for a second day on more signs of oversupply. Greek Finance Minister Yanis Varoufakis and euro zone