title: Error in QueryExpression with PartyList
body: <p>I'm trying to retrieve appointments whose "requiredattendees" contains on one of entities from account list. requiredattendees have a type of PartyList.
  My query looks like:</p>
  
  <pre><code>var query = new QueryExpression("appointment")
  {
        ColumnSet = columnSet,
        Criteria = new FilterExpression(LogicalOperator.Or)
  };
  </code></pre>
  
  <p>And adding conditions :</p>
  
  <pre><code>GetAccounts()
  .Select(a =&gt; new ConditionExpression("requiredattendees", ConditionOperator.Contains, a.Id))
  .ForEach(c =&gt; query.Criteria.AddCondition(c));
  
  
  a.Id is the account guid.
  </code></pre>
  
  <p>I'm getting following error:</p>
  
  <pre><code>Cannot add attribute requiredattendees of type partylist in a condition
  System.ServiceModel.FaultException`1[[Microsoft.Xrm.Sdk.OrganizationServiceFault, Microsoft.Xrm.Sdk, Version=5.0.0.0, Culture=neutral]]
  </code></pre>