v3.0.0

• Modify to use pypa/build for package build
• Add support for Python 3.9/3.10/3.11
• Drop support for Python 3.5/3.6
• Fix MANIFEST.in
• Add metadata to the package
• Remove BYTES_IO and UNICODE_LITERAL from timemachine.py
• Remove setup.cfg file
• Add docs extras

Full Changelog: v2.0.3...v3.0.0