Demonstrate use of individual modules in canonical `require('[module]/[path]')` form in `test_behavior_tree_2.js`.
Make the `{par,rules,seq}.js` module.export functions intantiate if called without `new`.
Add external links for extracurricular material.
Use `bSn` naming in `README.md`.
Break description in `README.md` into title and support stanzas.
Merge branch 'self-instantiating'
Merge branch 'extracurricular'