* remove outdated config file description
`example_config.json` was removed in f11da7b05b but the documentation
was still there, this removes the description from the README as well.
* add a note about how to use scripts with premium features
* Use YAML anchors to avoid repeating config blocks
* Use docker volumes to persist data for mysql
* Allow setting `FLEET_SERVER` (fixes#2127) when using the docker-compose file to spin up multiple osquery clients
Almost two years ago, we began referring to the project as Fleet, but there are
many occurences of the term "Kolide" throughout the UI and documentation. This
PR attempts to clear up those uses where it is easily achievable.
The term "Kolide" is used throughout the code as well, but modifying this would
be more likely to introduce bugs.
