Need to change lists, children and parents

A Section in a Rolon can contain Section Entries. And a Section Entry can be a PObject, like PString. But a Section is a list. Whoops! Lists need to be able to hold PObjects. Gotta fix that!

Meanwhile I've been thinking about the implementation of the Classifier Sections (CSec) Children and Parents. It is really pretty simple--these are just lists of handles which contain the unique names of the rolons. (This is just like the way the well known table works.) Forking and changeKey will require a bit of work, but that should not be too difficult.

I've also completed roughing out the implementation of Rolons, Units and Sections and even have a first working sample. I was planning on updating the docs now, but fixing list is a tad bit more important.