Put a "pubnote" in the sample article, consider deprecating/redefining "note"

[davidfarmer]

There is now a "pubnote" element in the sort-of structured bibtex-style source.

An example of this should go in the sample article.

A "note" should not go into the bibliography until we decide what is an "annotated bibliography". There may be more than one type of note in that application.

[davidfarmer]

replaces #505