v4.0.0 release

New release!

A lot of API changes, so it requires a new version number.

Important mentions

• Basics of GPEC algorithm, still in development
• Flash VT on the Python API
• Improved phase envelopes calculation

What's Changed

• Flash vt python by @SalvadorBrandolin in #145
• cibuildwheel new release fix by @SalvadorBrandolin in #146
• v4.0.0 by @fedebenelli in #143

Full Changelog: v3.1.0...v4.0.0