Various improvements related to packaging, distribution, CI and documentation. Notable changes:
- Added PEP 484 type stubs.
- Moved documentation to RTD.
- Fixed segfault when trying to access missing attributes of some constants.
- Fixed building error with Python 2.7 on Windows.
- Added CI pipelines for
manylinux2010
reference system and MacOS. - Reworked setup script, preparing for PEP 571 wheels.
- Prohibited installation for unsupported Python versions.
- Using
setuptools-scm
for dist version calculation from Git tags.