By Alexandra Alper WASHINGTON, June 29 (Reuters) - The U.S. Commodity Futures Trading Commission voted unanimously behind closed doors on Friday to approve two key measures outlining how U.S. swaps regulations will apply overseas. The measures had previously been slated for a public vote last Thursday, but the meeting was abruptly canceled due to last-minute negotiations between two Democratic commissioners. The second measure grants U.S. and foreign firms a delay in complying with c