Added wrapper around result (gotalk)

[emmaly]

This is regarding gotalk:

Added Result type, WrapResult func, Result.Result(), Result.Error(). This allows the JavaScript client to send responses back to the server when the JS is hosting the request.

Example of use:

gotalk.Handle("greet", func(in string, out *js.Object) {
	console.log("You've been greeted: " + in)
	r := gotalk.WrapResult(out)
	if rand.Intn(1) == 1 {
		r.Result({"greeting": "Greetings and/or Salutations!"})
	} else {
		r.Error("Sir, I said Good Day.")
	}
})