PG | 1h 50m | Comedy, Teenage Coming of Age | August 11, 1973 “American Graffiti,” the 1973 landmark teen drama that was a game-changer in the history of American cinema, celebrates its 50th anniversary this year. Opening credit roll in the high school film that begat all classic American high school films, “American Graffiti.” (Lucasfilm Ltd./The Coppola…