metal-stack v1.0.0

See original release note at https://github.com/metal-stack/releases/releases/tag/v1.0.0

After seven years of production, and with the core components of the metal stack finally migrated to API V2, we would like to mark this stage as v1.0.0.

Please find the blog post about the release on https://metal-stack.io/.

Thanks everyone who uses and contributes to metal-stack! 🍻