By Parisa Hafezi DUBAI (Reuters) -Iran on Monday accused arch-foe Israel of sabotaging its key Natanz nuclear site and vowed revenge for an attack that appeared to be latest episode in a long-running covert war. Iran said the person who caused an electricity outage in one of the production halls at the underground uranium enrichment plant had been identified. “Necessary measures are being taken to arrest this person,” Iranian state media reported, without giving further details. The incident occurred amid diplomatic efforts by Iran and the United States to revive Tehran’s 2015 nuclear deal wit…