For two years in a row this country’s film-lovers have been treated to the rare spectacle of Lebanese directors vying for Oscars. Last year Lebanon had its first brush with the Oscars when Ziad Doueiri’s fourth feature, “The Insult,” was nominated for Best Foreign Language Oscar. This year “Capernaum,” Nadine Labaki’s third feature, earned the same nomination. No trophies came home. Why?..