title: Add documentation to entity framework generated entities
body: <p>T4 enerate for me some entities like this : </p>
  
  <pre><code>public partial class Use
  {
  
      public int UseId { get; set; }
      public int ProgramId { get; set; }
      public System.DateTime InUseDate { get; set; }
  }
  </code></pre>
  
  <p>i whant to add documentation to this entity. i proceed like folowing:</p>
  
  <pre><code>[MetadataType(typeof(UseData))]
  public partial class Use { 
  
  }
  public class UseData
  {
      /// &lt;summary&gt;
      /// This is an ID
      /// &lt;/summary&gt;
      [Display(
          Name = "Use ID",
          Description = "This is an ID Desc")
      ]
      public int UseId;
  }
  </code></pre>
  
  <p>but VS autocomplete dont show me the summary of my UseIdattribute. </p>
  
  <p>any ideas</p>