Added FAQ-Entry making clear, that AWS Elasticsearch service is not supported

#78

Author: Chris Wiechmann

CHANGELOG.md

@@ -11,6 +11,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ### Changed
 - Log-Retention-Period for Trace-Messages from 75 days to 30 days [#77](https://github.com/Axway-API-Management-Plus/apigateway-openlogging-elk/issues/77)
 
+### Added
+- Added FAQ to make clear, that AWS Elasticsearch service is not supported [#78](https://github.com/Axway-API-Management-Plus/apigateway-openlogging-elk/issues/78)
+
 ## [2.1.1] 2021-02-05
 ### Fixed
 - Race-Condition, causing wrong organization assigned to API under heavy load [#75](https://github.com/Axway-API-Management-Plus/apigateway-openlogging-elk/issues/75)

README.md

@@ -1181,6 +1181,11 @@ Yes, all indicies are configured to have one replica and therefore it's safe to
 
 Tests show that Filebeat can send more than 3,000 events per second to Logstash instances. Tests show that Filebeat can send more than 2,200 events per second to Logstash instances. Of course, this number also depends on the event type. Trace messages can be processed faster than OpenTraffic event logs, for example. You can find an example [here](#imgs/stack-monitoring/stack-monitoring-beats-instances.png).
 
+### Can I use AWS Elasticsearch service?
+
+No, the solution does not support AWS Elasticsearch Service because some important features that are part of X-Pack are not supported by AWS. For example, index lifecycle management ([ILM](https://www.elastic.co/guide/en/elasticsearch/reference/current/index-lifecycle-management.html)).
+
+
 ## Known issues
 N/A