Fluent bit logging

This PR enables logs for all workers and services in grafana. It uses a lightweight raw exec fluent-bit task for each task group to ship the group's log files to influxdb. Additionally, the fluent-bit task of the monitoring group ships the logs of nomad, consul, and supervisord.

Important changes are:

• Install fluent-bit into the nomad/consul docker image, so that is available for each nomad job
• Change the influxdb network mode to bridge so that the influxdb entrypoint can setup the log database on startup using a hardcoded port. The script will create the database only if no database is configured before startup
• Increase memory of the influxdb task
• The grafana dashboard is replaced with a new one, see screenshot (the health check for the workers are currently not working)