Show team and repo badges on README

This patch adds the team's and repository's badges to the README file.
The motivation behind this is to communicate the project status and
features at first glance.

For more information about this effort, please read this email thread:

http://lists.openstack.org/pipermail/openstack-dev/2016-October/105562.html

To see an example of how this would look like check:

https://gist.github.com/7d9f14fa125fa35b52bc840eb94828b2

Change-Id: I5f6a3351469516aa81d5eb0fe7c842fe35d1433a

README.rst

@@ -1,3 +1,12 @@
+========================
+Team and repository tags
+========================
+
+.. image:: http://governance.openstack.org/badges/python-swiftclient.svg
+    :target: http://governance.openstack.org/reference/tags/index.html
+
+.. Change things from this point on
+
 Python bindings to the OpenStack Object Storage API
 ===================================================