Updating Helm 3 on the cluster

The main goal of this issue to discuss the switching to Helm 3 in the near future. The main advantages of the new version are that it doesn't use tiller and there is no separate user management anymore. So it should be more simple and secure. The new version depends on the kubernetes API only. I'm not an expert in this field, but this is how I can interpret the changes.

Note: This is a major version update so it can break things!

Currently, the version of the Helm is fixed to v2.14.3. Accordingly in the configuration of gitlab-ci yml file the image: dtzar/helm-kubectl:2.14.3 should be used. To prevent any modification of tiller the helm init --upgrade command should be avoided.

Possible issues:

• The old deployments are not available after updating Helm. So it looks like that each deployment require a "clean start".
• In theory, the charts are backwards compatible they must be tested before switching to the new version