“All God does is watch us and kill us when we get boring. We must never, ever be boring” (Chuck Palahniuk). I think that Chuck Palahniuk must be a fan of Leos Carax’s films. Because the diminutive French filmmaker’s “Holy Motors,” which is competing for the Palme D’Or, is never boring as his new film shows. “Holy Motors” represents everything that’s cinema ought to be: poetic, unpracticed in following convention and filled with mystery. He-