Several commit to limit the review :
webapp: code format
webapp: improve access log parsing
- fix a hardcoded path to the apache log file, filebeat was not reading it when the vhost name is not webapp.
- add an environment field to easily identify the origin of a log entry
- add a vhost field to easily regroup the logs of a vhost (can be also added on varnish side)
logstash: Add support an optional duration on apache logs
It will allow to monitor the front responses time per requests.
The conversion of the request and duration fields to integer is
mandatory to use them in some aggregation.
The ES indexes will have to be reindexed if we want to have the full
history.
apache: Add the request duration on access logs
It will add some visibility on the monitoring
Related to T2787