Normalize glanceclient requested service url

Some proxy or gateway softwares, e.g. jumpgate [0], use url-pattern
based approach to match which hanlding logic needs to be triggered for
particular service calling when it received a http(s) call as a
middleman. The change fixed an issue which caused glanceclient send out
the request to a dis-normal url, which contains duplicated "/".

The change removed a wrong and duplicated code snippet from curl logging
function as well.

[0] http://goo.gl/yt52X1

Change-Id: Ic8b3920e11d400771ead7f9c44b615f10b4a5cef
Signed-off-by: Zhi Yan Liu <zhiyanl@cn.ibm.com>
Merge "Normalize glanceclient requested service url"