Changes to Create a playlist folder

added the new optional query request parameter type

added the new optional request property type (media type: application/json)

added the new optional request property type (media type: application/x-www-form-urlencoded)

added the required property playlist_folder/items/hidden to the response with the 200 status

added the required property playlist_folder/items/type to the response with the 200 status

endpoint added