Do not store last_updated in the config file anymore

app.go

@@ -106,6 +106,7 @@ func run(args options) {
 			log.Printf("Couldn't load filter %d contents due to %s", filter.ID, err)
 			// clear LastUpdated so it gets fetched right away
 		}
+
 		if len(filter.Rules) == 0 {
 			filter.LastUpdated = time.Time{}
 		}