This work was supported by institutes of the National Center for Scientific Research (CNRS), the University Pierre and Marie Curie (UPMC), and the University of Lyon in France, and in the United States by the U.S. Department of Energy’s Office of Science (Office of High Energy Physics); the Gordon and Betty Moore Foundation; the National Science Foundation; an Henri Chrétien International Research Grant administered by the American Astronomical Society; and the France-Berkeley Fund.