Generate helm chart templates from components module

[shreyas-s-rao]

How to categorize this issue?

/area open-source usability
/kind enhancement

What would you like to be added:
Generate helm chart templates from components module, to avoid double maintenance of druid components in both components module as well as helm charts. The helm charts templates for the druid components can be generated via make generate-helm-templates, which will be called by make generate.

This may be tricker than it looks, since it involves generating the templating constructs that helm charts provide, so that consumers of the helm chart can use it as is. We need to evaluate whether this is worth doing, with the sole benefit of avoiding double maintenance. cc @unmarshall

Why is this needed:
Explained in #974