This patch changes the following to support helm chart spec and
to test instantiate/terminate cnf with helm chart.
* Add `extra` field to vims db.
* Add `setup-helm` task to ansible-playbook roles.
[On controller-k8s node]
* Create and setup helm user for executing helm command.
* Install helm.
* Create folder for putting local helm chart.
* Enable password authentication in sshd_config and restart sshd.
[On controller node]
* Update Vims DB of vim-kubernetes to modify extra field that include
helm access information.
Implements: blueprint helmchart-k8s-vim
Change-Id: Iaf7c11c5bedb77e9cd21074be2b4f73528aa2ce7
d7a13ce18a