Grace Cossington Smith’s Interiors   How she loved doors! Her interiors are full of them. It’s as if her front door has admitted us to her house and the intimacy of its rooms with their chests of drawers and beds and chairs and sewing machine, prosaic enough one would think, except that all are suffused with colour. And in the rooms are open doors leading to her studio or the big garden with its lawn and massed trees. Then there are the wardrobes with their open doors and mirrors reflecting the verandah and more garden, all awash with her signature…