v0.8.11

• Build wheels using oldest-supported-numpy instead of the latest numpy. In this way, the generated wheels will be forward-compatible with newer numpy versions
• Remove runtime dependency on setuptools

Other packaging and testing changes:

• Use pyproject.toml to specify build requirements
• Execute build_ext when running sdist.
• Use PyPA build package to build the sdist.
• Move most metadata from setup.py to setup.cfg .
• Test built packages by importing