Because of the change from using setuptools.pkg_resources to using
importlib, we no longer need a runtime dependency on setuptools. It is
still required, however, for running setup.py.
Currently, you must read ten paragraphs about writing renewal hooks
before you find that most distributions will automatically renew certs
for you. This is burying the lede in a major way; moving it up to the
header seems a better choice.
