Update README

Author: lgallard

README.md

@@ -166,6 +166,7 @@ No modules.
 | <a name="input_cloudwatch_log_enabled"></a> [cloudwatch\_log\_enabled](#input\_cloudwatch\_log\_enabled) | Change to false to avoid deploying any Cloudwatch Logs resources | `bool` | `true` | no |
 | <a name="input_cluster_config"></a> [cluster\_config](#input\_cluster\_config) | Cluster configuration of the domain | `any` | `{}` | no |
 | <a name="input_cluster_config_availability_zone_count"></a> [cluster\_config\_availability\_zone\_count](#input\_cluster\_config\_availability\_zone\_count) | Number of Availability Zones for the domain to use with | `number` | `3` | no |
+| <a name="input_cluster_config_cold_storage_options_enabled"></a> [cluster\_config\_cold\_storage\_options\_enabled](#input\_cluster\_config\_cold\_storage\_options\_enabled) | Indicates whether to enable cold storage for an Elasticsearch domain | `bool` | `false` | no |
 | <a name="input_cluster_config_dedicated_master_count"></a> [cluster\_config\_dedicated\_master\_count](#input\_cluster\_config\_dedicated\_master\_count) | Number of dedicated master nodes in the cluster | `number` | `3` | no |
 | <a name="input_cluster_config_dedicated_master_enabled"></a> [cluster\_config\_dedicated\_master\_enabled](#input\_cluster\_config\_dedicated\_master\_enabled) | Indicates whether dedicated master nodes are enabled for the cluster | `bool` | `true` | no |
 | <a name="input_cluster_config_dedicated_master_type"></a> [cluster\_config\_dedicated\_master\_type](#input\_cluster\_config\_dedicated\_master\_type) | Instance type of the dedicated master nodes in the cluster | `string` | `"r5.large.elasticsearch"` | no |