title: NotMapped annotation doesn't work with EF6 CodeFirst
body: <p>I struggle with my data model. I don't want to store some fields to the DB with EF CodeFirst so I did:</p>
  
  <pre><code>using System.ComponentModel.DataAnnotations.Schema;
  
  [NotMapped]
  public int MyProp{ get; set; }
  </code></pre>
  
  <p>I also set AutomaticMigrationsEnabled to true but after Update-Database the field appears in the DB.</p>
  
  <p>I use EntityFramework 6.1.3.</p>
  
  <p>So what did I worng? Thanks in advance for your help</p>