Spell check `README.md` and rewrite somewhat.

Rewrote the `README.md` so it is not rediculously wrong, but it is
incomplete, and lacks meaningful examples.

Ran spell check against `REAMDE.md` and Docco.

See #55.
Closes #32.
Move supporting libraries to root directory.

Got rid of the `lib` directory because the project is so small,
organizing it into sub-directories makes it harder to understand the
project layout at a glance. Tests still belong in `t` though.

Closes #44.
Merge branch `tidy` into `master`.