DUBLIN (Reuters) - Atlantis, the legendary island nation over whose existence controversy has raged for thousands of years, was actually Ireland, according to a new theory by a Swedish scientist. Atlantis, the Greek philosopher Plato wrote in 360 BC, was an island in the Atlantic Ocean where an advanced civilization developed some 11,500 years ago until it was hit by a cataclysmic natural disaster and sank beneath the waves. Geographer Ulf Erlingsson, whose book explaining his theory will be published next month, says the measurements, geography, and landscape of Atlantis as described by Plato match Ireland almost exactly. "I am...