Make ping return false on any TransportError

Closes elastic#388

Author: honzakral

elasticsearch/client/__init__.py

@@ -210,7 +210,10 @@ def ping(self, params=None):
  Returns True if the cluster is up, False otherwise.
  `<http://www.elastic.co/guide/>`_
  """
- return self.transport.perform_request('HEAD', '/', params=params)
+ try:
+ return self.transport.perform_request('HEAD', '/', params=params)
+ except TransportError:
+ return False
 
  @query_params()
  def info(self, params=None):