L2SS-1052: remove elk entries

README.md

bootstrap/sbin/rebuild_system_from_scratch.sh

docker-compose/Makefile

docker-compose/elk-configure-host/Dockerfile

docker-compose/elk.yml

docker-compose/elk/Dockerfile

docker-compose/elk/kibana/default-objects.ndjson

docker-compose/elk/logstash/conf.d/02-beats-input.conf

docker-compose/elk/logstash/conf.d/03-syslog-input.conf

docker-compose/elk/logstash/conf.d/04-tcp-input.conf

docker-compose/elk/logstash/conf.d/10-syslog.conf

docker-compose/elk/logstash/conf.d/11-nginx.conf

docker-compose/elk/logstash/conf.d/20-parse-grafana.conf

docker-compose/elk/logstash/conf.d/21-parse-prometheus.conf

docker-compose/elk/logstash/conf.d/22-parse-tango-rest.conf

docker-compose/elk/logstash/conf.d/23-parse-maria-db.conf

docker-compose/elk/logstash/conf.d/30-output.conf

...tango-prometheus-exporter/code/tango-prometheus-client.py

...ationcontrol/tangostationcontrol/devices/docker_device.py