added sample parameters for jwt

config.sample.json

@@ -2,7 +2,13 @@
 create a db_config.json here's 
 */
 {
-  "config":{
-    "db_params":{"uri":"postgresql://user:password@host:port/dbname"}
+  "config": {
+    "db_params": {
+      "uri": "postgresql://user:password@host:port/dbname"
+    },
+    "jwt": {
+      "secret": "secret",
+      "expire_seconds": 3600
+    }
   }
 }