add Azure support and a bit of refactoring

[idanlevin]

@arthur-c two important notes:

1. The S3 usage here is deprecated and needs to be removed (I added a TODO there)
2. There is one breaking change I couldn't avoid with creating the TLS secrets, since I wanted to be able to use helm install <chart> --set-file key=/path/to/file and couldn't have done it without adding b64enc

[fsschmitt]

This might solve #10

[camprr]

I'd love to implement this based on the following article (https://itnext.io/monitoring-kubernetes-workloads-with-prometheus-and-thanos-4ddb394b32c) , any news on this being merged?

[arthur-c]

Hello @camprr , currently I don't have the time to include PRs in this project, but this chart has been forked many times and some forks are more active and advanced than this project.