Added user_realm_name to the docs

README.md

@@ -114,7 +114,8 @@ from keycloak import KeycloakAdmin
 keycloak_admin = KeycloakAdmin(server_url="http://localhost:8080/auth/",
                                username='example-admin',
                                password='secret',
-                               realm_name="example_realm",
+                               realm_name="master",
+                               user_realm_name="only_if_other_realm_than_master",
                                client_secret_key="client-secret",
                                verify=True)