title: Serialize Array of Vector2 with Json.NET
body: <p>I am trying to use Json.NET on Unity to serialize a class.<br>
  The class <em>Polygon</em> contains an <em>Array</em> of <em>Vector2</em> but i only want to serialize the x and y variables of Vector2 class, that's why I'm using the JsonConverter attribute.</p>
  
  <p><strong>Sample class:</strong></p>
  
  <pre><code>public class Polygon
  {
      public int count { get; set; }
  
      [JsonConverter(typeof(Vector2Converter[]))]
      public Vector2[] points { get; set; }
  }
  </code></pre>
  
  <p>It gives me this error at runtime:</p>
  
  <blockquote>
    <p>MissingMethodException: Method not found: 'Default constructor not
    found...ctor() of
    JsonDotNet.Extras.CustomConverters.Vector2Converter[]</p>
  </blockquote>
  
  <p>Anyone have any suggestions?</p>