title: MongoDB does Birt support aggregate cursor
body: <p>When I use Mongodb aggregation with Birt I had the error below:</p>
  
  <pre><code>org.eclipse.datatools.connectivity.oda.OdaException: 
  Unable to run the Aggregate command operation.
  Check that your connected MongoDB server is version 2.2 or later. ;
      com.mongodb.CommandResult$CommandFailure: command failed [aggregate]: 
  { "serverUsed" : "/xxx.xx.xx.xxx:27017" , 
    "errmsg" : "exception: aggregation result exceeds maximum document size (16MB)" , 
    "code" : 16389 , "ok" : 0.0 , 
    "$gleStats" : { "lastOpTime" : { "$ts" : 0 , "$inc" : 0} , 
    "electionId" : { "$oid" : "557cd07784d145278edfba15"}}}
  </code></pre>