helm v3 as default and upgrade command

[webmutation]

Hi @bmoussaud, thanks a lot for supporting both helm versions.
There is just a couple of minor issues..

V3 would be preferred as default. and the update command in v2 will not accept --name as option
https://v2.helm.sh/docs/helm/#options-43

        if int(self.helmclient.version) == 2:
            parameters = "{chartName} --namespace {namespace}  --name {name} --version {chartVersion}".format(**values)
        elif int(self.helmclient.version) == 3:
            parameters = "{name} {chartName} --namespace {namespace} --version {chartVersion}".format(**values)

I also found some helm command changes. I created a PR for you to review.