- Using Viper brings us lots of nice features, but also one problem:
- We had to switch StringArray flags to StringSlice flags, which
- allow to use multiple flag values comma-separated in a single flag, but also
- split flag values that contain a comma into separate parts (and we cannot handle issues that arise due to this)
- so if you rely on commas in your flag values (e.g. for `--env X=a,b,c`), please consider filing an issue or supporting <https://github.com/spf13/viper/issues/246> and <https://github.com/spf13/viper/pull/398>
-`--env X=a,b,c` would be treated the same as `--env X=a`, `--env b`, `--env c`
### Features & Enhancements
- use [viper](https://github.com/spf13/viper) for configuration management
- takes over the job of properly fetching and merging config options from
- CLI arguments/flags
- environment variables
- config file
- this also fixes some issues with using the config file (like cobra defaults overriding config file values)
- add JSON-Schema validation for the `Simple` config file schema
- new config version `k3d.io/v1alpha2` (some naming changes)
- Communicate managed registry using the LocalRegistryHostingV1 spec from [KEP-1755](https://github.com/kubernetes/enhancements/blob/0d69f7cea6fbe73a7d70fab569c6898f5ccb7be0/keps/sig-cluster-lifecycle/generic/1755-communicating-a-local-registry/README.md)
- interesting especially for tools that reload images, like Tilt or Skaffold
- **Note**: The config file format (& feature) might still be a little rough around the edges and it's prone to change quickly until we hit a stable release of the config