Add template-dependency command

[sumo-drosiek]

Get override configuration

There could be scenarios when you want to get the configuration of the subcharts (prometheus-operator, fluent-bit, etc.).

Command template-dependency takes part of the upstream values.yaml file basing on the given key:

 kubectl run template-dependency \
  -it --rm \
  --restart=Never -n sumologic \
  --image sumologic/kubernetes-tools \
  -- template-dependency prometheus-operator

This command will return our configuration of prometheus-operator ready to apply for the prometheus-operator helm chart.

You can add additional parameters (like --version=1.0.0) at the end of the command.
List of supported arguments is compatible with helm show values.

[perk]

Hm the get-override seems a bit detached from the original template command.
I think it should be something like template-dependency.

This way original template gives the whole config while template-dependency gives config for the dependency only.

[sumo-drosiek]

It can give you configuration of any part of the values.yaml, not only dependencies

[perk-sumo]

I like it now 👍

[frankreno]

LGTM