#14 Add file is Dirty functionality

[Timothy Farrar]

Hey it would also be nice if we could have a callback that would be fired the first time that a key is pressed inside the editor, thus enabling us to know if the file is dirty or not, or whatever else we wanted to do at that point. Another feature simular to this, but a bit different that I would like to have is the ability to have a callback whenever an editor recieves focus.

Great work on the editor by the way, and hope these features can be added witout too much trouble.

[Timothy Farrar]

this would be similar to the feature in the editor when we have multiple files open.