title: Ignore navigation property when mapping in Automapper
body: <p>Having these 2 classes as an example:</p>
  
  <pre><code>public class Product
  {
      public int Id {get; set;}
      public int CategoryId {get; set;}
  }
  
  public class ProductDTO
  {
      public int Id {get; set;}
      public int CategoryId {get; set;}
      public Category Category {get; set;}
  }
  </code></pre>
  
  <p>How can I ignore <code>ProductDTO.Category</code> when mapping bidrectionally?</p>