Synced jsonutils from oslo-incubator

The sync includes change that drastically enhances performance on Python
2.6 with fresh simplejson library installed.

The latest commit in oslo-incubator:
- 0f4586c0076183c6356eec682c8a593648125abd

Change-Id: Ib3dc0b713ed90396919feba018772243b3b9c90f
Closes-Bug: 1314129
Make neutronclient parse keystone v3 endpoints correctly

Import keystone access module to handle various verion of keystone
catalog.

Change-Id: Ie8de15da6341cdb3af73c0fa8753f7e754bf6275
Closes-bug: 1295056
Merge "Synced jsonutils from oslo-incubator"
Merge "Make neutronclient parse keystone v3 endpoints correctly"