TOKYO (AP) — Thousands of Japanese marched to celebrate the switching off of the last of their nation's 50nuclear reactors Saturday, waving banners shaped as giant fish that have become a potent anti-nuclear symbol. Japan was without electricity from nuclear power for the first time in four decades when the reactor at Tomarinuclear plant on the northern island of Hokkaido went offline for mandatory routine maintenance. After last year's March 11 quake and tsunami set off meltdowns at the Fukushima Dai-ichi plant, no reactor halted for checkups has been restarted amid public worries about the safety of nuclear technology. "Today...