Create maintenance branch for 0.9 releases #76
Description
vObject 0.9.x continues to support CPython 2.7, as well as 3.8 and later. This branch will be retained, and bug fixes back-ported, as required by users. I expect very little activity here: PyPI download stats suggest nearly everyone has moved to Python 3.x now.
Future development will focus only on Python 3.x, and will occur in the 1.x series of releases.
- Rename 'master' to 'main'
- Create 'shipping-0.9' branch
- Set up CI to build and test both branches
- Begin tooling modernisation on 'main' branch, leading to 1.0.0 release