Not sure we want to have this in the repo. There are actually quite nice editors for JSON [out there](http://www.jsoneditoronline.org/), so it might be easier to use these together with the template you gave below? (P.S: if I find an hour or two, I basically know how to get this editor into ipynb, so that from within your notebook you could say:
    
    jsoneditor.open("bla.json")

and it would give you the same interface, but __inside__ the ipynb.