1. Department of Astrophysics/IMAPP, Radboud University , PO Box 9010, NL-6500 GL Nijmegen, the Netherlands
2. Department of Physics, University of Warwick , Gibbet Hill Road, Coventry, CV4 7AL, UK
3. Department of Physics, University of Auckland , Private Bag 92019, Auckland, New Zealand
4. School of Physics, O’Brien Centre for Science North, University College Dublin , Belfield, Dublin 4, Ireland
5. Inter-University Institute for Data Intensive Astronomy, Department of Astronomy, University of Cape Town , Private Bag X3, Rondebosch 7701, South Africa
6. South African Astronomical Observatory , P.O. Box 9, 7935 Observatory, South Africa
7. Institute for Astronomy , KU Leuven, Leuven, Belgium
8. SRON, Netherlands Institute for Space Research , Sorbonnelaan 2, NL-3584 CA Utrecht, the Netherlands
9. Physics Department, Lancaster University , Lancaster LA1 4YB, UK