anchor.diff:          ("Castle.Core","4.0.0");
           ("FAKE","4.0.0");
           ("log4net","1.2.10")]
  -        |> Seq.sortBy (fun (key,_) -> key)
  -
  -    result
  -    |> Seq.sortBy (fun (key,_) -> key)
  +        |> Seq.sortBy fst
  +
  +    result
  +    |> Seq.sortBy fst
       |> shouldEqual expected
        
   [<Test>]
  
positive.code:         [("Castle.Core-log4net","4.0.0");
          ("Castle.Core","4.0.0");
          ("FAKE","4.0.1")]
          |> Seq.sortBy (fun (key,_) -> key)
  
      result
      |> Seq.sortBy (fun (key,_) -> key)
      |> shouldEqual expected
      
  [<Test>]
  
negative.code:         ("FAKE","4.0.0");
          ("log4net", "1.2.10");
          ("Newtonsoft.Json", "7.0.1")]
          |> Seq.sortBy fst
  
      result
      |> Seq.sortBy fst
      |> shouldEqual expected
      
  [<Test>]
  