update readme with basic config settings setup information

README.md

@@ -113,6 +113,16 @@ AWS Elastic Beanstalk Setup (Docker)
 	14. Wait for beanstalk to update the environment.
 	15. Try it out by entering the domain of the form \*.elasticbeanstalk.com found at the top of the dashboard into your browser. You can also map your own domain if you wish. 
 
+Configuration Settings
+----------------------
+
+There are a few configuration settings you might want to fiddle with when setting up your instance of Mattermost. You can edit them in ./config/config.json or ./config/config/config_docker.json if you're running a docker instance.
+
+* *EmailSettings*:*ByPassEmail* - If this is set to true, then users on the system will not need to verify their email addresses when signing up. In addition, no emails will ever be sent.
+* *ServiceSettings*:*UseLocalStorage* - If this is set to true, then your Mattermost server will store uploaded files in the storage directory specified by *StorageDirectory*. *StorageDirectory* must be set if *UseLocalStorage* is set to true.
+* *ServiceSettings*:*StorageDirectory* - The file path where files will be stored locally if *UseLocalStorage* is set to true. The operating system user that is running the Mattermost application must have read and write privileges to this directory.
+* *AWSSettings*:*S3*\* - If *UseLocalStorage* is set to false, and the S3 settings are configured here, then Mattermost will store files in the provided S3 bucket.
+
 Contributing
 ------------