Add BVMC 2016 paper on SBIR
This paper is not present in the list, and I feel that it is relevant to the development of sketch-based image retrieval architectures in deep learning: [Deep Multi-task Attribute-driven Ranking for Fine-grained Sketch-based Image Retrieval
](http://www.bmva.org/bmvc/2016/papers/paper132/index.html)

By the way, thanks for the carefully curated collection of papers on this topic!