Changelog:
===========
- Upgrade zstd source code from v1.5.5 to v1.5.6
- Fix pyzstd_pep517 parameter name in get_requires_for_build_wheel
- Deprecate support for Python version before 3.8 and stop building wheels for them
- Minor fixes in type hints
- Refactor README & CHANGELOG files
Signed-off-by: Wang Mingyu <wangmy@fujitsu.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>
