Ukraine's opposition leaders signed an EU-mediated peace pact with President Viktor Yanukovich on Friday, winning a raft of concessions in a delicate deal to end violence that killed at least 77 people and turned the capital into a battle zone. By nightfall, opposition leaders who signed the deal were addressing peaceful crowds from a stage in Independence Square, which for the past 48 hours had become an inferno of blazing barricades, where protesters were shot dead by police snipers. But...