Official Helm chart based on kube-thanos

[stevehipwell]

I'm interested in an official Helm chart based on the code in kube-thanos and am happy to contribute to get this created. I have the following potential solutions, in no particular order, listed below.

• New thanos-io/helm-charts repo with kube-thanos chart added (based off kube-thanos source)
• Add charts folder to kube-thanos and create the chart there
• Create the chart at https://github.com/prometheus-community/helm-charts/, as kube-state-metrics have done

If none of these options are desirable/possible I will be creating a chart in my own repo but this is only a fall-back option.