Refactor http request/response logging

Using the --debug flag or the GLANCECLIENT_DEBUG env var, a user will
see http requests and responses in great detail. Requests are formed
into proper curl commands while responses are printed just as they would
as if the curl request provided were executed. Response bodies will not
be printed if they are application/octet-stream.

Change-Id: I9c9c5d6ec9f481091c944e596d073da3739795b6

glanceclient/v1/client.py

@@ -13,16 +13,11 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import logging
-
 from glanceclient.common import http
 from glanceclient.v1 import images
 from glanceclient.v1 import image_members
 
 
-logger = logging.getLogger(__name__)
-
-
 class Client(http.HTTPClient):
     """Client for the OpenStack Images v1 API.