Expose events ttl for ceilometer

We need to be able to update the event_time_to_live based
on how long evenets should be kept in mongodb.

Change-Id: I0948438207f85afc95f2ba33d93a6a5d7b1af257

puppet/services/ceilometer-base.yaml

@@ -44,6 +44,10 @@ parameters:
     default: false
     description: Whether to store events in ceilometer.
     type: boolean
+  CeilometerEventsTTL:
+    default: -1
+    description: Number of seconds before database can expire the events data
+    type: number
   Debug:
     default: ''
     description: Set to True to enable debugging on all services.
@@ -91,6 +95,7 @@ outputs:
               - "%{hiera('tripleo::profile::base::database::mysql::client_bind_address')}"
         ceilometer_backend: {get_param: CeilometerBackend}
         ceilometer::metering_secret: {get_param: CeilometerMeteringSecret}
+        ceilometer::event_time_to_live: {get_param: CeilometerEventsTTL}
         # we include db_sync class in puppet-tripleo
         ceilometer::db::sync_db: false
         ceilometer::keystone::authtoken::project_name: 'service'