Only config which contains os-apply-config data should be written
to the top level config structure. This change will only top-level
configs which are in the group os-apply-config or the default group
Heat::Ungrouped.
This tripleo-heat-templates change will specify a group for all
config resources https://review.openstack.org/#/c/91731/ however
the expected top-levels will still be written out without this
change.
This change is to fix heat software config when the config is not
json.
Change-Id: I16e42825121cf4968d4b0f0d266f4f6daa962921
Closes-Bug: #1299109
b066d4cc85