It’s not quite Star Trek, where food can be made to materialize just by talking into a machine. But restaurant guests at a new Holiday Inn in Duluth, Ga., can now place their meal orders electronically. The so-called Emenu — really a tablet PC connected wirelessly to a computer in the hotel — provides photos and nutritional info on menu items. Customers can tally the calories, carbs, and price of their meals before they order, then zap the request to the kitchen. The Emenu also translates that data into Spanish and into euros.