update README

Author: bobevenup

README.md

@@ -149,7 +149,7 @@ json_logging.config_root_logger()
 ```
 
 # 3. Configuration
-logging library can be configured by setting the value in json_logging
+logging library can be configured by setting the value in json_logging, all configuration must be placed before json_logging.init method call
 
 Name | Description | Default value
  --- | --- | ---

example/flask_sample_app.py

@@ -7,6 +7,7 @@
 
 app = flask.Flask(__name__)
 json_logging.ENABLE_JSON_LOGGING = True
+# json_logging.CREATE_CORRELATION_ID_IF_NOT_EXISTS = False
 json_logging.init(framework_name='flask')
 json_logging.init_request_instrument(app)
 
@@ -15,7 +16,6 @@
 logger.setLevel(logging.DEBUG)
 logger.addHandler(logging.StreamHandler(sys.stdout))
 
-
 @app.route('/')
 def home():
     logger.info("test log statement")