Refactor trovilo job design

[johscheuer]

Currently trovilo supports multiple jobs (e.g. to gather information for Prometheus and for Grafana) since trovilo is designed to run inside Kubernetes environments I don't actaully see a benefit in supporting multiple jobs (and adding the complexity). From my perspective trovilo should always be used as a sidecar to the according service like in the Prometheus example: https://github.com/inovex/trovilo/blob/master/examples/k8s/deployment.yaml#L60

Are there any reasons why we should keep to support multiple jobs?