1. Centre for Extragalactic Astronomy, Department of Physics, Durham University , DH1 3LE , UK
2. Institute for Astronomy and Astrophysics, National Observatory of Athens , V. Paulou & I. Metaxa, Pendeli, 11532 , Greece
3. Max Planck Institute for Extraterrestrial Physics, Giessenbachstrasse , D-85741 Garching , Germany
4. Excellence Cluster Universe , Boltzmannstr. 2, D-85748 Garching , Germany
5. Donostia International Physics Center (DIPC), Manuel Lardizabal Ibilbidea , 4, 20018, San Sebastián , Spain
6. Institute for Astronomy, University of Edinburgh, Royal Observatory , Edinburgh EH9 3HJ , UK
7. School of Physics and Astronomy, University of Leicester, University road , Leicester LE1 7RJ , UK
8. School of Physics and Astronomy, University of Southampton , Highfield, Southampton SO17 1BJ , UK
9. INAF-Observatory of Rome , via di Frascati 33, Monteporzio Catone, I-00074 Rome , Italy
10. Department of Physics and Astronomy, Dartmouth College , Hanover, NH 03755 , USA
11. SISSA , Via Bonomea 265, I-34136 Trieste , Italy
12. Dipartimento di Fisica e Astronomia ‘Augusto Righi’ , Alma Mater Studiorum - Universitá di Bologna, Via Gobetti 93/2, I-40129 Bologna , Italy
13. INAF-Osservatorio di Astrofisica e Scienza dello Spazio via Gobetti 93/3 , I-40129 Bologna , Italy
14. Instituto de Astrofísica de Canarias, Calle Vía Láctea , s/n, E-38205 La Laguna, Tenerife , Spain
15. Departamento de Astrofísica, Universidad de La Laguna , E-38206 La Laguna, Tenerife , Spain
16. Department of Physics, University of Bath, Claverton Down , Bath BA2 7AY , UK