Shogun helm charts

[simonseyock]

This introduces helm-charts for the current SHOGun stack.

❗ THIS PR NEEDS TO BE SQUASH MERGED ❗

[ahennr]

Generally: 👍 and nice work @simonseyock

However, some notes regarding helm usage: Did you use an actual helm template (e.g. using helm create shogun-admin)? Could you please check this again, as the Chart api version seems to be out of date.

Just as a further idea: Would it make sense to add a chart that combines all the components required for a SHOGun setup in one single chart, so that an working preconfigured SHOGun can be installed via `helm install my-shogun shogun-repo/shogun, for example?

[simonseyock]

I started from an existing helm chart and used the existing docker-compose as a cross-reference. Good catches. I will update the versions.

Currently I am working on pre-configuring the values so each chart can be started one by one and hopefully it will work by default.