LOS ANGELES The first-time director and cast of unknowns of the acclaimed sci-fi thriller “District 9” have given Hollywood a late-summer box-office boost. The Sony release produced by “Lord of the Rings” director Peter Jackson led the weekend with a $37 million debut, according to studio estimates Sunday. “District 9” is the debut feature from commercial and music-video director Neill Blomkamp, who co-wrote the tale about extraterrestrials forced by humans to live in squalor in a ghetto in South Africa. More..