title: Select option not filled with values which are mapped from other table
body: <p>I have a mapping between two models, <code>Movie</code> and <code>Place</code>.
  when i now create a from <code>movieForm</code> and fill in a already created <code>Movie</code> and open then a view with that <code>movieForm</code> all textfields and select's are populate except the value which mappes the <code>Place</code> to the <code>Movie</code>.
  in the below example the categorie is correct selected in the "select" in the view but the place are not selected.</p>
  
  <p>What can be the problem?
  and how can i resolve this?</p>
  
  <hr>
  
  <h3>Movie Model</h3>
  
  <pre><code>@Entity
  public class Movie extends Model {
  
      @Id
      public Long id;
      ...
      @Required
      @Formats.NonEmpty
      public EnumCategorie categorie = EnumCategorie.FILM;
      @ManyToOne
      public Place place;
  
      ...
  }
  </code></pre>
  
  <h3>Place Model</h3>
  
  <pre><code>@Entity
  public class Place extends Model {
      @Id
      public String name;
      ...
  }
  </code></pre>
  
  <h3>The Controller</h3>
  
  <pre><code>public class Movies extends Controller {
      public static Result edit(Long id) {
          Movie movie = Movie.find.byId(id);
          Form&lt;Movie&gt; movieForm = form(Movie.class).fill(movie);
          return ok(movieCreate.render(movieForm,
                  placeForm, "edit"));
      }
  </code></pre>
  
  <h3>The View</h3>
  
  <pre class="lang-scala prettyprint-override"><code>@form(routes.Movies.save(option)) {
          &lt;fieldset&gt;
          ...
          @select(movieForm("categorie"),
              options(Movie.categories),
              '_label -&gt; "Categories", '_default -&gt; "-- Choose a categorie --",
              '_showConstraints -&gt; false,
              'class -&gt; "controls")
          @select(movieForm("place"),
              options(Place.places),
              '_label -&gt; "Places", '_default -&gt; "-- Choose a place --",
              '_showConstraints -&gt; false,
              'class -&gt; "controls")
          ...
          &lt;/fieldset&gt;
  </code></pre>
  
  <hr>