static void Main(string[] args)
        {
            Wyam.Common.Tracing.Trace.AddListener(new System.Diagnostics.TextWriterTraceListener(Console.Out));
            var engine = new Engine();

            engine.Namespaces.Add("Wyam.Docs");     // or razor will complain
            engine.FileSystem.InputPaths.Add(new DirectoryPath(@"C:\temp\wyam.test\content"));
            engine.FileSystem.InputPaths.Add(new DirectoryPath(@"C:\temp\wyam.test\input"));
            engine.FileSystem.OutputPath = new DirectoryPath(@"C:\temp\wyam.test\site");
            var dr = new Docs();

            dr.Apply(engine);
            engine.Execute();
        }