Relevant to AtlasMap standalone usage. A user with an openapi document needs to export JSON schema for involved types when using AtlasMap. It'd be nice to be able to import an openapi document directly into the AtlasMap UI. Most likely an openapi document will contain more than one definition so we may need to offer the user a list of types so that the user can choose what should be imported. It should probably be possible to import either source or target documents.