Sync with oslo-incubator caed79d

This syncs python-keystoneclient with oslo-incubator commit hash
caed79d8239679cb74476bb0d9e5011b4fcc39da

First, remove the existing code to cleanup:
 $ rm -r keystoneclient/openstack/*

Then, sync from oslo-incubator:
 $ python update.py ../python-keystoneclient

Commits since last sync (2640847):
----------------------------------
1173e46 Remove ValueError when accessing sys.modules
90ae24b Remove redundant default=None for config options
18f2bc1 Enforce unicode json output for jsonutils.load[s]()
4a777e5 Fix warnings in doc build for apiclient

Related-Bug: #1315523
Closes-Bug: #1314129
Change-Id: Id53ea2d4828e81bc6270f186849f391e7bc73101
Merge "Sync with oslo-incubator caed79d"