Add soft param ceilometer_gnocchi_archive_policy

Add soft param ceilometer_gnocchi_archive_policy=default
and move it to system.defaults.openstack

Change-Id: I7b813ccb0bf71842b68f6a9d69382c2a06111f92
Related-Prod: PROD-23721 (PROD:23721)
diff --git a/ceilometer/server/backend/gnocchi.yml b/ceilometer/server/backend/gnocchi.yml
index 6ebf45f..d9f40fb 100644
--- a/ceilometer/server/backend/gnocchi.yml
+++ b/ceilometer/server/backend/gnocchi.yml
@@ -12,7 +12,7 @@
       publisher:
         gnocchi:
           enabled: true
-          url: "gnocchi://?filter_project=${_param:ceilometer_gnocchi_filter_project}"
+          url: "gnocchi://?filter_project=${_param:ceilometer_gnocchi_filter_project}&${_param:ceilometer_gnocchi_archive_policy}"
           publish_metric: true
           # filter_project is deprecated since queens
           filter_project: ${_param:ceilometer_gnocchi_filter_project}
diff --git a/defaults/openstack/init.yml b/defaults/openstack/init.yml
index f9b189e..75bb601 100644
--- a/defaults/openstack/init.yml
+++ b/defaults/openstack/init.yml
@@ -65,6 +65,7 @@
     ceilometer_old_version: ${_param:openstack_old_version}
     ceilometer_version: ${_param:openstack_version}
     ceilometer_upgrade_enabled: ${_param:openstack_upgrade_enabled}
+    ceilometer_gnocchi_archive_policy: default
     # Gnocchi
     gnocchi_memcache_security_enabled: ${_param:openstack_memcache_security_enabled}
     gnocchi_memcache_secret_key: ''