* Minor improvements
* Document empty list vs null for users without privileges
* Change the wording for null values
* Add talk by Oleksii in Atmosphere
* Define sidecars in the operator configuration.
Right now only the name and the docker image can be defined, but with
the help of the pod_environment_configmap parameter arbitrary
environment variables can be passed to the sidecars.
* Refactoring around generatePodTemplate.
Original implementation of per-cluster sidecars by @theRealWardo
Per review by @zerg-junior and @Jan-M
zerg-junior
Dmitry Dolgov
Oleksii Kliukin