This patch moves the json.loads(body) call in the
HTTP response handling to after the check for non-
200-300 return codes. This gets rid of the
ValueError exception raise when you hit, for instance,
a 400 or 404.
Also changes a number of logger.exception() calls to
logger.debug() calls, since some exceptions are expected
and should not be logged as exceptions per-se.
fixes LP bug#1067512
Change-Id: If66fb1846ddc19da5bc2f15c6e0dd09019a56932
a6102fe0b9