3.2.1

Fixes for build, deployment, and docs

• Use explicit package list to make sure unumpy is included (#232)
• Use setuptools-scm to make sure all files are in the source distribution (#235)
• updates to configuration for and links to readthedocs documentation. (#239)
• use double backticks more uniformly in docs. (#240)
• fixes to README.rst to allow it to render (needed for PyPI upload) (#243)