Editable Tree Model

[kloffy]

Ok, I did get it to work. Heres the editable version of the simple tree model.

[kloffy]

And here's the application to run it.

Edit: I would not advise on using this code as is. I'm just happy that the basic functionality is there and I have a pretty good understanding of how to implement an editable tree model now. If I have some free time I'll properly implement the necessary methods (e.g. to support multiple columns).