- Both `js-yaml` and `yaml-languageserver-parser` have been replaced with
`yaml`.
- `jsonc-parser` has been externalized.
- All defaults are now specified explicitly.
- The new property `yamlVersion` has been added to match
`yaml-language-server`. The default is `1.2`.
- `DiagnosticsOptions` properties are now sorted alphabetically and
documentation has been enhanced.
Closes#117