Updated openstack/openstack
Project: openstack/keystone  ff130069f26ac50db15bab66a40f89b8dafe9dc0

replaced unicode() with six.text_type()

According to https://wiki.openstack.org/wiki/Python3 unicode()
should be replaced with six.text_type().

Change-Id: I7e6119d66b7ad51e4a8ee7b3d8ce4188e321a08b