Additional Kolla config overrides for Nova and Horizon

etc/kayobe/kolla/config/nova.conf

+[DEFAULT]
+# Don't enable new nova-compute automatically
+enable_new_services=False
+
+[libvirt]
+images_type=flat
+snapshot_image_format=qcow2
+live_migration_downtime=2000
+live_migration_timeout_action=force_complete
+cpu_mode=host-model
+
+[oslo_messaging_notifications]
+driver = log
+
+[notifications]
+notification_format = versioned
+notify_on_state_change = vm_and_task_state
+default_level = INFO
+notification_format = versioned