wysiwyg referencability

With referencability extended to all the children of an item, you can get a lot of unexpected name collision which is not apparent when you run the topics command.

When I implement the enhanced inc command, I am going to try restricting referencability to items which are visibile. You will still be able to reference the children of visible items with item/child name notation (a qualified name) and grandchildren with the item/child/grandchild notation.

This should make for fewer suprises. And that's a good thing.

I'll also note that this reduction in the size of the referencable namespace will also speed thing up a bit. And that can be important when displaying a long page with a lot of references, as this namespace is processed against every reference for proper coloring.