Grafana: support multiple Grafana organizations in context of dashboard provisioning.

[jkroepke]

Ref: #3240

Problem

The grafana helm charts currently supports only one dashboard provider. Multiple providers are supported.

However, just give the possibility to configure multiple providers are not enough. PVC configuration and more is manatory. The end-user experience lacks, because the all dashboards needs to be annotated with grafana_folder annotation that must be begin with /tmp/dashboards.

Solution

To avoid the usage of grafana_folder annotation, multiple sidecars needs to be deployed. At least each single provider/org needs an own sidecar. Form end-user perspective, only a correct label on the dashboard ConfigMap must be set.