hnb stands for Hierarchical NoteBook. It is a console (ncurses)
program to organize many kinds of data in one place, including
addresses, TODO lists, ideas, book reviews, brainstorming,
speech outlines, etc. It stores data in XML format, and is
capable of native export to ASCII and HTML.
Approved by wiz.
This closes my own PR 18233 (the package was provided there).