Add dividers to defaults/main.yml
Add dividers to defaults/main.yml

This patch adds dividers in the defaults/main.yml to separate
configuration defaults for the RHEL 6 & 7 STIG content. The
vast majority of the configuration variables will differ between
both of these STIG versions, so it doesn't make sense to intermix
the defaults.

Implements: blueprint security-rhel7-stig
Change-Id: Ib46f9d2bba40f861b4bb22c08315d28c35e618ee

major/openstack-ansible-security,major/openstack-ansible-security