Add a helm chart to install tesoro

[myspotontheweb]

This PR replaces #24

Background

When reviewing this project I found the setup details off-putting. I felt a Helm chart would make it simpler to install the software. It would also automate:

• Details of setting up a secure self signed certificate.
• How to configure credentials for external secret providers like Vault

Motivation

I am considering utilizing Tesoro as a better (gitops compatible) secret management solution. I like how embedded references encode all the details of accessing the secret. The only comparable solution. in my option, would be External Secrets.

While I acknowledge the authors use kapitan to do their manifest generation, in our case we use Helm to install our cluster's platform services.

Enhancements

• Ideally this Helm chart should be published in a Helm repository, making it easier to consume by users. Might also increase the profile of the kapitan project
• Include documentation on how credentials for AWS KMS + GCP KMS could be configured.

Known issues

This helm chart will not work on Kubernetes v1.19

• Kubernetes v1.19 API changes
• #93264

Latest version of helm is using go 1.14

$ helm version
version.BuildInfo{Version:"v3.4.1", GitCommit:"c4e74854886b2efe3321e185578e6db9be0a6e29", GitTreeState:"clean", GoVersion:"go1.14.11"}

[uberspot]

Nice addition! :)

[ademariag]

@myspotontheweb also join us on #kapitan on kubernetes slack so we can help you with your evaluation

[myspotontheweb]

Regrettably I cannot join the kubernetes slack channel. I have requested an invite but received no email confirmation. I had the same problem joining the cloud native channel for KubeCon this week.
I will continue to try and hopefully we'll be able to communicate more meaningfully soon.