Drop use of 'oslo' namespace package

The Oslo libraries have moved all of their code out of the 'oslo'
namespace package into per-library packages. The namespace package was
retained during kilo for backwards compatibility, but will be removed by
the liberty-2 milestone. This change removes the use of the namespace
package, replacing it with the new package names.

The patches in the libraries will be put on hold until application
patches have landed, or L2, whichever comes first. At that point, new
versions of the libraries without namespace packages will be released as
a major version update.

Please merge this patch, or an equivalent, before L2 to avoid problems
with those library releases.

Blueprint: remove-namespace-packages
https://blueprints.launchpad.net/oslo-incubator/+spec/remove-namespace-packages

Change-Id: Ie85c87d157a7f6e7c9984000ecf96e943c393a6f

zaqar/tests/unit/transport/wsgi/v2_0/test_subscriptions.py

@@ -16,7 +16,7 @@ import uuid
 
 import ddt
 import falcon
-from oslo.serialization import jsonutils
+from oslo_serialization import jsonutils
 
 from zaqar import tests as testing
 from zaqar.tests.unit.transport.wsgi import base

zaqar/transport/validation.py

@@ -16,7 +16,7 @@
 
 import re
 
-from oslo.config import cfg
+from oslo_config import cfg
 import six
 
 from zaqar.i18n import _

zaqar/transport/websocket/driver.py

@@ -13,7 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from oslo.config import cfg
+from oslo_config import cfg
 
 try:
     import asyncio