Clean up cookbook for bp/clean-up-attr-for-mq-and-db

This change removes the attributes we'll be moving to openstack-common
and changes reference of those attributes to reflect new (more
consistent) namespace. We also fix a broken test which doesn't properly
converge after changing a node attribute.  Lastly, we handle the rabbit
mq attribute use_ssl.

Change-Id: I12b9c33f89eb35a66bae7420340aff10efd18b1c
Implements: blueprint clean-up-attr-for-mq-and-db