gFlex version 1.2.0

Major improvements (as determined by AW)

• Updated for Python 3, and now, Python 3.10+
• Updated build and configuration for current standards
• argparse for CLI
• Update testing and CI: Travis --> GitHub actions
• Overall professional cleaning of code by @mcflugen

What's Changed

• Update repository for newer Pythons, packaging standards by @mcflugen in #44

New Contributors

• @mcflugen made their first contribution in #44

Full Changelog: v1.1.1...v1.2.0