Update README.md

Author: begarco

README.md

@@ -1,5 +1,5 @@
 # TaskOverflow
-   Grails project at ISIMA by Benoit Garçon
+   Grails project at ISIMA by Benoît Garçon
 
 ## Configuration server
 
@@ -14,5 +14,24 @@ By default the server will be reachable on [http://localhost:666](http://localho
    java "-Dgrails.env=dev" -jar .\build\libs\conf-0.1.war
    ```
 
-## Health check
-Health check is available at [http://localhost:666/health](http://localhost:666/health).
+## Configuration server Health Check
+Health check is available at [http://localhost:666/health](http://localhost:666/health).
+
+  ## Stateless application
+  This application is totally stateless.
+
+  ## Authentification mechanism
+  This application is secured through spring-security-rest.
+
+  ## Feature Flipping
+  The Feature Flipping is implemented: it use the [configuration server](http://github.com/TaskOverflow/conf) of this project. To test the feature flipping on a feature, you just need to switch between 'ok' and 'ko' in the corresponding file in [conf/data/](http://github.com/TaskOverflow/conf/data). Warning: it is important to run the configuration server from root (like it is said in the corresponding README). Every five seconds the client ping each features to know if the feature is activated.
+   
+  ## Health check
+  The complete Health Check is available at [http://localhost:8080/health](http://localhost:8080/health).
+  Some simplified Health Check are available for each features (user, badge, tag, question) at http://localhost:8080/featureName/healthcheck, it is used in Circuit Breaker feature.
+
+  ## Circuit Breaker
+  The Circuit Breaker is implemented with the help of previously described feature healthcheck. Every five seconds the client ping each features to know if they respond 200 or an error. In the opened mode the circuit waits 20 seconds. If you want to play with the circuit breaker, you have to launch the server with `grails run-app` and modify the code returned by healthcheck() action of the desired controller. Or you can just break the server.
+
+  ## Graceful Degradation
+  If there is a problem, some features are simply deleted from the UI (badge, tag), other features are replaced by new third party service : when user feature is down a list of random people is displayed, when question feature is down random gif of cats are displayed instead.