title: can I limit consumption of kafka-node consumer?
body: <p>It seems like my kafka node consumer:</p>
  
  <pre><code>var kafka = require('kafka-node');
  var consumer = new Consumer(client, [], {
       ...
      });
  </code></pre>
  
  <p>is fetching way too many messages than I can handle in certain cases. 
  Is there a way to limit it (for example accept no more than 1000 messages per second, possibly using the pause api?)</p>
  
  <ul>
  <li>I'm using kafka-node, which seems to have a limited api comparing to the Java version</li>
  </ul>