Move to newer version of python-swiftclient

The 2.0.x release of python-swiftclient includes SSL certificate
verification. This is desired for https://review.openstack.org/#/c/75927/

Change-Id: I3d6371a31c07c4e31da72edf9dd71537c8e58d23
Merge "Move to newer version of python-swiftclient"