Add ability to install helm charts

This patch adds ability to install helm charts and to add helm
repos. It was decided to take python code from salt-formula-helm
instead of using pyhelm module since it uses grpc and requires a
tunnel to tiller since tiller is not exposed and operates with its
client using portforward api.

Change-Id: I992abcf7eb035342a01dca838438ae7e2115fda0
Related-PROD: PROD-28361
7 files changed