1. IAG, Departamento de Astronomia, Universidade de São Paulo , SP 05508-090 São Paulo , Brazil
2. Department of Astronomy and Astrophysics, University of Chicago , 5640 S Ellis Avenue, Chicago, IL 60637 , USA
3. Kavli Institute for Cosmological Physics, University of Chicago , Chicago, IL 60637 , USA
4. Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology , Cambridge, MA 02139 , USA
5. Steward Observatory, University of Arizona , 933 N. Cherry Ave., Tucson, AZ 85721-0065 , USA
6. Observatories of the Carnegie Institution for Science , 813 Santa Barbara Street, Pasadena, CA 91101 , USA
7. Center for Astrophysics, Harvard and Smithsonian , 60 Garden Street, Cambridge, MA 02138 , USA