title: MetaData Response - Broker hostname is wrong
body: <p>I use python-kafka's SimpleConsumer to listen to a topic in kafka broker. Kafka broker is running on a machine with its hostname as BROKER_HOST. 
   Now, SimpleConsumer requests for topic metadata from the broker BROKER_HOST for a topic TOPIC &amp; gets a tuple </p>
  
  <pre><code>   (Broker metadata, Topic metadata)
  </code></pre>
  
  <p>Broker metadata comes as,</p>
  
  <pre><code> {0: BrokerMetadata(nodeId=0, host='localhost', port=9092)}
  </code></pre>
  
  <p>and ideally, host value must be BROKER_HOST(<code>hostname</code> shell cmd confirms it) but it is localhost... </p>
  
  <p>``How does the broker metadata for a topic get into kafka system? And obviously, this breaks the system since my consumer tries to connect to 9092 on its localhost.</p>