Create an ansible role to install Tiller

Currently the anchore role installs tiller/helm, however this should be broken out to a separate role as it is a common dependency (e.g., it is required by the opensource jenkins role as well)

Also move this task which is currently in the opensource-jenkins role into the new helm/tiller role:

- name: Upgrade tiller service account permissions (OCP Only)
  command: "{{ ocp_cli }} adm policy add-cluster-role-to-user cluster-admin {{ tiller_service_account }} -n {{ tiller_namespace }}"
  when: ocp_installed
  changed_when: false

cc: @jhurlocker @kreap @pminchew