Replace use of pkg_resources

[shuds13]

• Fix this: DeprecationWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html on install

• May go with updating to use pyproject.toml

[jlnav]

May be a good idea for v2.0; plus I believe lots of misc .dotfiles can be put in pyproject.toml too

[jmlarson1]

Moving dotfiles content elsewhere could be nice.