It's Christmas! Well, it was Christmas. Reviews are like Christmas cards - better late than never. I hope that all of you have a great New Year.I thought it was high time to cover an Agatha Christie on this blog - and given I love short stories, this was the first thing I turned to. I should mention that, between Poirot and Miss Marple, my favourite is the spinster sleuth of St. Mary Mead. These thirteen stories mark the debut of Miss Marple, before…