Add setting for clients certificate

Author: Saeid Hassan-Abadi

roles/icingadb_redis/defaults/main.yml

@@ -65,3 +65,4 @@ icingadb_redis_rdb_save_incremental_fsync: 'yes'
 #icingadb_redis_tls_cert: /etc/ssl/certs/host.crt
 #icingadb_redis_tls_key: /etc/ssl/private/host.key
 #icingadb_redis_tls_ca: /etc/ssl/certs/root-ca.crt
+#icingadb_redis_client_certificate:

roles/icingadb_redis/templates/icingadb-redis.conf.j2

@@ -227,4 +227,5 @@ rdb-save-incremental-fsync {{ icingadb_redis_rdb_save_incremental_fsync }}
 tls-cert-file {{ icingadb_redis_tls_cert }}
 tls-key-file {{ icingadb_redis_tls_key }}
 tls-ca-cert-file {{ icingadb_redis_tls_ca }}
+tls-auth-clients {{ icingadb_redis_client_certificate }}
 {% endif %}