Export `pyclipper.__version__` string (40). Removed long-deprecated `SCALING_FACTOR` global variable.
1.2.1
No code changes in the main library. Only added wheels for Python 3.9.
1.2.0
Release the Global Interpreter Lock (GIL) while doing more CPU intensive calls to ClipperLib (union, difference, intersection, minkowski, offset, etc), to allow Python apps to better parallelize when using threading (29, 30).
1.1.0.post2
Dropped support for setuptools_scm_git_archive. No code changes, only a minor change in setup process when building from source. Wheels are unaffected.