Add ability to get version information in python

* A user can access glanceclient.__version__ to get a string
  representing the version of the installed library.
* Add openstack-common's 'version' module.

Change-Id: Ib14c561d8ac0b126617a20acfbd5fdb61c54f2c7

glanceclient/__init__.py

@@ -0,0 +1,19 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+#    Copyright 2012 OpenStack LLC
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from glanceclient import version
+
+__version__ = version.version_info.deferred_version_string()