add/remove/reorder + save columns for object renderer

[GoogleCodeExporter]

Say right click -> add property, gives you list from class.

Would also be awesome to be able to save the view to a file, and restore it
later.  Note we then need to land issue 95 first.

Original issue reported on code.google.com by cgwalt...@gmail.com on 17 Jan 2008 at 8:53