1. Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK
2. Faculty of Physics and Astronomy, Astronomical Institute (AIRUB), Ruhr University Bochum, German Centre for Cosmological Lensing, D-44780 Bochum, Germany
3. Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK
4. Argelander-Institut für Astronomie, German Centre for Cosmological Lensing, Auf dem Hügel 71, D-53121 Bonn, Germany