Newly-elected Athens mayor Costas Bakoyannis, scion of one of Greece’s most powerful political families, took his oath of office Sunday pledging to turn the crisis-battered capital into “a safe, clean and bright” European metropolis.“Over the next four years I pledge to be a servant to Athenians,” the 41-year-old told a crowd of supporters at the ceremony.“Athens is an idea … as proud as we are of this city’s historical past, we are saddened by its present state,” Bakoyannis said, adding that…