Fixes bug on Windows related to a wrong API url

Fixes Bug #1079323

python-glanceclient (latest repository code) fails on Windows due to a
malformed API url. This error is due to the usage of os.path.normpath(),
which should not be used for URLs as it swaps "/" with "\" on Windows.

The fix consists in using posixpath.normpath().
Please see also https://bugs.launchpad.net/nova/+bug/1077125 and related
commit.

Change-Id: Iaa643bd579963ad9ffbf10674973cbca75d435ac

glanceclient/common/http.py

@@ -16,7 +16,7 @@
 import copy
 import httplib
 import logging
-import os
+import posixpath
 import socket
 import StringIO
 import struct
@@ -142,7 +142,7 @@ class HTTPClient(object):
         conn = self.get_connection()
 
         try:
-            conn_url = os.path.normpath('%s/%s' % (self.endpoint_path, url))
+            conn_url = posixpath.normpath('%s/%s' % (self.endpoint_path, url))
             if kwargs['headers'].get('Transfer-Encoding') == 'chunked':
                 conn.putrequest(method, conn_url)
                 for header, value in kwargs['headers'].items():