Fixed an error due to some misconception.

I was thinking about the typeof null==="object" language flaw there was no need
to take care of it here. Actually if documents were kept clean of all null
objects I wouldn't need to think of it in the first place.
Expanded _views/fields-values to flat field hierarchy.

Fields with dots are quoted, as always. This works well with _list/tabulate, as
long as no quotes are involved. Since I am expanding and contracting fields on
multiple instances, this should go into a library.
Simplified flat-hierary-generation.

Both code samples had good and bad parts in it, so a combination wastes the
least amount of lines.