title: XmlSerializer enumeration deserialization failing on (non existent) whitespace
body: <p>I have an object I'm deserializing which contains an enum 'JourneyPatternLinkDirectionEnumeration', it's used as a value for a node 'Direction'.</p>
  
  <p>When 'Direction' is specified with a value, or not specified and it's represented in xml as</p>
  
  <pre><code>&lt;Direction /&gt;
  </code></pre>
  
  <p>Everything works fine. However, if it's in the xml as</p>
  
  <pre><code>&lt;Direction&gt;&lt;/Direction&gt;
  </code></pre>
  
  <p>I get the following error:</p>
  
  <blockquote>
    <p>"Instance validation error: '' is not
    a valid value for
    JourneyPatternLinkDirectionEnumeration."</p>
  </blockquote>
  
  <p>My code is as follows:</p>
  
  <pre><code>var xmlTextReader = new XmlTextReader(xmlDocUri);
  xmlTextReader.WhitespaceHandling = WhitespaceHandling.None;
  xmlTextReader.Normalization = false;
  
  var serializer = new XmlSerializer(typeof(T),  typeof(T).Assembly.GetTypes());
  
  ouput = (T)serializer.Deserialize(xmlTextReader);
  </code></pre>
  
  <p>Any thoughts? Is there a better way to do this.</p>
  
  <p>(Sorry I can't post the full code, the xml doc is a 65000-line TransXchange doc)</p>