Update Code Block node from a separate response

It was impossible to create and update CBN in Custom node workspace. This PR contains appropriate fix
@pboyer `lastValue` for CBN is updated correctly with this code. I consider no update is needed here

![cbn](https://cloud.githubusercontent.com/assets/7658189/5218573/251a797a-7657-11e4-93d1-7cec1bd68cdd.png)