title: Json.Net PopulateObject Appending list rather than setting value
body: <p>I am using Json.Net for .Net 4.5 and when using populate object on the following object it increments the List's with the content of the json rather than setting its value.</p>
  
  <p><strong>Json.Net</strong></p>
  
  <pre><code>JsonConvert.PopulateObject(string, object)
  </code></pre>
  
  <p><strong>Class</strong></p>
  
  <pre><code>class MySettingSubClass
  {
      public List&lt;string&gt; MyStringList1 = new List&lt;string&gt;(){"one", "two", "three"}
  }
  
  class MySetting
  {
      public string MyString = "MyString";
      public int MyInt = 5;
      public MySettingSubClass MyClassObject = new MySettingSubClass();
      public List&lt;string&gt; MyStringList2 = new List&lt;string&gt;{"one", "two", "three"};
  }
  </code></pre>
  
  <p>When they initially load, all is correct, however reloading from JSON both MyStringLists are duplicated <code>"one", "two", "three", "one", "two", "three"</code></p>