Born and bred Hastonian, Steph Warren is one of the United Kingdom’s leading authorities on the graffiti and street art movement, having worked with both Banksy and Ben Eine back in the noughties as a young woman at the forefront of a very male-orientated and secretive world. Owner of Stella Dore Art Gallery (previously based in East London, now in St Leonards). I caught up with the gallerist, curator, art and mural facilitator