update readme for max-lifetime

README.md

@@ -102,8 +102,8 @@ Note that net/https and openssl libraries must be available:
 Note that [gssapi](https://github.com/zenchild/gssapi) library must be available:
 
     client = WebHDFS::Client.new('hostname', 14000)
-    # or if you want to use client delegation token with renewing per 8 hours
-    client = WebHDFS::Client.new('hostname', 14000, username, nil, nil, nil, {}, 8)
+    # or if you want to use client delegation token with renewing per 8 hours and delegation token max-lifetime is 7 days
+    client = WebHDFS::Client.new('hostname', 14000, username, nil, nil, nil, {}, 8, 168)
 
     client.kerberos = true
     client.kerberos_keytab = "/path/to/project.keytab"