Plot: With the rise of electronic books, is the final chapter about to be written in the long love story between books and their readers? Will the app take the place of the traditional book? Alan Yentob discusses the subject with writers Alan Bennett, Douglas Coupland, Ewan Morrison and Gary Shteyngart, publisher Gail Rebuck, agent Ed Victor and librarian Rachael Morrison. They also smell books, making precise notes about the distinctive aroma of each