Subscriber content previewBy JAKE COYLEAP Film Writer[enlarge] In the pantheon of sad-sack protagonists, Oscár is a triumph. In Simón Mesa Soto’s “A Poet,” Oscár Restrepo (Ubeimar Rios) is a failed Columbian writer who keeps a photo of the author José Asunción Silva above his mantle. Silva died at age 30, and even Oscár would admit his own career would be a lot better if he had died young, too.