Hampus Lindwall, Charlemagne Palestine and Cory Arcangel outside St Mary's Church, Walthamstow. Photo Rosanna Sutcliffe Art Night is a free, contemporary art festival, taking place over one night, once a year, in a different area of London.  This year the festival is on the night of Saturday 22nd June, and centred on Walthamstow and Kings Cross in North London.  Festival curator Helen Nisbet had seen an evening of contemporary organ music organised last year in Paris by Cory Archangel and  Hampus Lindwall, and invited them to create an event for Art Night 2019 based around the…