dojo_concepts.html now works with adding and removing property.
Cannot edit belongs_to and class name though.

TODO: Still need dialog to create class with custom names.
Added loading of concepts from file.
Working on controller's constructor.
Updated Branch, Section and ListItem.
to be displayed in dojo_concepts.html.

But ListItem has no constructor at the moment, need to consult http://dojotoolkit.org/reference-guide/1.8/quickstart/writingWidgets.html
again.