Release with GitHub Workflow

[dbrgn]

This replaces #170 and builds upon the work by @black7375, thanks a lot!

Additional changes:

• Clean up scripts
• Create (draft) release before uploading assets
• Find release for current tag, don't simply pick the latest
• Add Windows builds
• Add checksums for binaries

The result is a pretty awesome release pipeline:

[black7375]

It's clean and looks good. happy new year :fireworks: