Do the sexual politics of Ibsen's A Doll's House belong to a bygone era? Hardly, says Carrie Cracknell, director of a new film that recasts the play's heroine as an ad exec and mother longing to escapeEarlier this year, I directed a production of Ibsen's A Doll's House for the Young Vic in London, starring Hattie Morahan in the role of Nora. Nora is a woman conditioned and formed by the patriarchal society of 18…