doc(faq): transfered questions to README

These discussion threads are valuable, but no longer active.

* fixes go-openapi#164
* fixes go-openapi#23

Signed-off-by: Frederic BIDON <fredbi@yahoo.com>

README.md

@@ -29,3 +29,26 @@ The object model for OpenAPI specification documents.
 > This [discussion thread](https://github.com/go-openapi/spec/issues/21) relates the full story.
 >
 > An early attempt to support Swagger 3 may be found at: https://github.com/go-openapi/spec3
+
+* Does the unmarshaling support YAML?
+
+> Not directly. The exposed types know only how to unmarshal from JSON.
+>
+> In order to load a YAML document as a Swagger spec, you need to use the loaders provided by
+> github.com/go-openapi/loads
+>
+> Take a look at the example there: https://pkg.go.dev/github.com/go-openapi/loads#example-Spec
+>
+> See also https://github.com/go-openapi/spec/issues/164
+
+* How can I validate a spec?
+
+> Validation is provided by [the validate package](http://github.com/go-openapi/validate)
+
+* Why do we have an `ID` field for `Schema` which is not part of the swagger spec?
+
+> We found jsonschema compatibility more important: since `id` in jsonschema influences
+> how `$ref` are resolved.
+> This `id` does not conflict with any property named `id`.
+>
+> See also https://github.com/go-openapi/spec/issues/23