Add log output about HTTP calls in cinderclient

This patch enables heat to output the details of requests
to cinder and responses from cinder
(including 'x-openstack-request-id' in the response header)
to the log.

Change-Id: I714c87e538bc3a51dce6a48e584824cf7f954bcf
Closes-bug: #1329613
Merge "Add log output about HTTP calls in cinderclient"