Adding the messages feature in the core editor class

![screenshot from 2014-04-13 21 18 52](https://cloud.githubusercontent.com/assets/514557/2691780/68a6a854-c38c-11e3-8e08-d1e01d5143e5.png)

Adding the messages feature. I have split the js file into two parts but I'll send that as a separate PR so as to not mix up these changes with that.