Builders began putting up the festival grounds for Munich’s famous Oktoberfest on Monday morning, about two and a half months before the beer-soaked festivities will kick off on the Theresienwiese fairgrounds, known locally as the Wiesn. Oktoberfest, which bills itself as the largest folk festival in the world and draws millions of visitors each year, is scheduled to run from September 21 to October 6. This year, set-up work began even earlier than usual, after the operators of the tents and kitchens at the festival complained that preparations have become increasingly complex. A big remaining…