enhance swiftclient logging

* log to debug for successes and info for errors
* remove dead code, neither body or raw_body are sent in kwargs
* include resp.reason and response headers in logging
* remove trailing \n in logging. users who want them can set logging.basicConfig(format=FORMAT)
* add --info option to swift cli

Change-Id: If07af46cb377f3f3d70f6c4284037241d360a8b7
Merge "enhance swiftclient logging"