title: Parse Cloud Code retrieving a user with objectId
body: <p>I am trying to get the user object from objectId. I know the objectId is valid. But I can get this simple query to work. What is wrong with it? user is still undefined after the query.</p>
  
  <pre><code>var getUserObject = function(userId){
      Parse.Cloud.useMasterKey();
      var user;
      var userQuery = new Parse.Query(Parse.User);
      userQuery.equalTo("objectId", userId);
  
      userQuery.first({
          success: function(userRetrieved){
              console.log('UserRetrieved is :' + userRetrieved.get("firstName"));
              user = userRetrieved;               
          }
      });
      console.log('\nUser is: '+ user+'\n');
      return user;
  };
  </code></pre>