title: Nullable int type allowed in Settings.settings?
body: <p>I have a property that I'd like to type as <code>int?</code> in my Settings.settings file.  When I use <code>int?</code> I get a runtime failure:</p>
  
  <p>System.NullReferenceException: Object reference not set to an instance of an object..</p>
  
  <p>I can use a string type as a workaround where a check for null works, but I have to parse the string and handle errors when the parse doesn't work.</p>
  
  <p>Being able to set the value to null allows me to keep the property documented in the settings file while making it obvious that no value has been set.  When not set I use a programmed default value:</p>
  
  <pre><code>int? configuredNumberOfLimits = Settings.Default.RequiredNumberOfLimits;
  if ( configuredNumberOfLimits == null  )
  {
      requiredNumberOfLimits = DEFAULT_REQUIRED_NUMBER_LIMITS;
  }
  </code></pre>