title: jackson do not deserialize child list object
body: <p>I receive the following JSON: </p>
  
  <pre><code>{"firstName":"charle","lastName":"charly","books":[{"title":"navle"}]}
  </code></pre>
  
  <p>And i try to parse it into this Jackson object:</p>
  
  <pre><code>@JsonIgnoreProperties(ignoreUnknown = true)
  public class Person {
  
    @Id @ObjectId
    private String _id;
  
    private String firstName;
    private String lastName;
    List&lt;Book&gt; books; 
  // getters/setters ..
  }
  </code></pre>
  
  <p>The problem is that the Object "Person" that i get have always an empty list of books ! </p>
  
  <p>What i'm missing ? </p>