title: Lambda to create EMR Cluster don't fire the cluster creation
body: <p>I'm trying to run a λ code that creates a cluster, but nothing happens, maybe I'm misunderstanding the usage on Node (since I'm not that familiar with it.)</p>
  
  <p>The function is as simple as:</p>
  
  <pre><code>// configure AWS Dependecies
  var AWS = require('aws-sdk');
  
  exports.handler = function(event, context) {
      // EMR Client
      var emr = new AWS.EMR({apiVersion: '2009-03-31', region: 'us-east-1'});
  
      var params = {... dozens of params describing jobs ...};
      var AWSRequest = emr.runJobFlow(params);
      AWSRequest
          .on('success', function(response){ console.log("success =&gt; " + response)})
          .on('error', function(response){ console.log("error =&gt; " + response)})
          .on('complete', function(response){ console.log("complete =&gt; "  + response)})
          .send( function(err, data){
              if (err) console.log(err, err.stack); // an error occurred
              else     console.log(data);           // successful response
          });
  
      context.done(null, 'λ Completed');
  };
  </code></pre>
  
  <p>I'm testing it with the <code>grunt-aws-lambda</code> grunt task and in the console, but nothing shows except for:</p>
  
  <pre><code>aws-emr-lambda$ grunt lambda_invoke
  Running "lambda_invoke:default" (lambda_invoke) task
  
  Message
  -------
  λ Completed
  
  Done, without errors.
  </code></pre>
  
  <p>Executing it from the AWS console results in the same output and no EMR Cluster is created.</p>
  
  <p>Any thoughts on this?</p>