title: unable to connect to remote host with rabbitmqadmin
body: <p>I'm trying to connect to a remote rabbitmq host using the cli rabbitmqadmin. </p>
  
  <p>The command I'm trying to execute is:</p>
  
  <pre><code>rabbitmqadmin --host=$RABBITMQ_HOST --port=443 --ssl --vhost=$RABBITMQ_VHOST --username=$RABBITMQ_USERNAME --password=$RABBITMQ_PASSWORD list queues
  </code></pre>
  
  <p>Before you ask: the environmental variables RABBITMQ_HOST, RABBITMQ_VHOST and so on are set... I double and triple checked this already.</p>
  
  <p>The error I get back is:</p>
  
  <pre><code>Traceback (most recent call last):
  File "/usr/local/sbin/rabbitmqadmin", line 1007, in &lt;module&gt;
  main()
  File "/usr/local/sbin/rabbitmqadmin", line 413, in main
  method()
  File "/usr/local/sbin/rabbitmqadmin", line 588, in invoke_list
  format_list(self.get(uri), cols, obj_info, self.options)
  File "/usr/local/sbin/rabbitmqadmin", line 436, in get
  return self.http("GET", "%s/api%s" % (self.options.path_prefix, path), "")
  File "/usr/local/sbin/rabbitmqadmin", line 475, in http
  self.options.port)
  File "/usr/local/sbin/rabbitmqadmin", line 451, in __initialize_https_connection
  context = self.__initialize_tls_context())
  File "/usr/local/sbin/rabbitmqadmin", line 467, in __initialize_tls_context
  self.options.ssl_key_file)
  
  TypeError: coercing to Unicode: need string or buffer, NoneType found
  </code></pre>
  
  <p>From the last line I assume it's a python related problem, my current python version is 2.7.12, if I try to connect to the local instance of rabbitmq with </p>
  
  <pre><code>rabbitmqadmin list queues
  </code></pre>
  
  <p>everything works fine. Any help is greatly appreciated thanks :)</p>