The first great film of the year is a small, and likely already out of the theaters, treasure written and directed by the genius behind 2004’s brilliant “The Station Agent.” Like its predecessor, “The Visitor” is a story about a journey from loneliness back into the real world of the living. In this case a recently widowed, middle aged professor, stuck somewhere between deep professional apathy and outright depression, is given a totally unexpected shot in the arm.