Update to 1.3.2
ChangeLog: https://github.com/sarugaku/shellingham/blob/1.3.2/CHANGELOG.rst
Add a minimal setup.py file -- the upstream package has switched to
the pep517 (https://www.python.org/dev/peps/pep-0517/) setup style,
and in the absense of built-in support for that, hack things so that
setuptools can still work.