public void CantCreateAnyOtherType()
       {
           KdbWriterFactory factory = new KdbWriterFactory(new WinRTCrypto(),
                    new MultiThreadedBouncyCastleCrypto(),
                    new SHA256HasherRT(),
                    new GZipFactoryRT());
 
           Assert.ThrowsException<NotSupportedException>(() =>  factory.CreateWriter(null));

       }
       public void CanCreateKdb4Writer()
       {
           KdbWriterFactory factory = new KdbWriterFactory(new WinRTCrypto(),
                    new MultiThreadedBouncyCastleCrypto(),
                    new SHA256HasherRT(),
                    new GZipFactoryRT());
           var kdb4Tree = new Kdb4Tree(new XDocument());
           var writer = factory.CreateWriter(kdb4Tree);

           Assert.IsInstanceOfType(writer, typeof(Kdb4Writer));
       }