Include the keystone client in the common recipe

The client is needed in the call to openstack-common's cli library,
identity_uuid, in the ruby_block.

Change-Id: I0d5dbb18eb57ea848baf91bfce0eaa23a3c860fa
Closes-Bug: #1330484
use new python_packages attributes from -common

*_python_packages attributes are being moved to -common in order to
remove the duplication from all the cookbooks which are using them

Change-Id: Id3c8a262f8ce177da71201f765afaa0e2c890e0e
Implements: blueprint move-python-db-client-attrs-to-common