* Add transaction pool docs.

* Extra docs.

* Apply suggestions from code review

Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>

* Expand on some review comments.

* Update README.md

Fixed typos / spellings

Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>
Co-authored-by: Squirrel <gilescope@gmail.com>