Add config_owner_user and config_owner_group to group_vars/all,
which is user and group of Kolla configuration files in /etc/kolla.

Add become to post-deploy playbook.

Add become to only neccesary tasks in roles:
- certificate
- common
- destroy
- haproxy
- mariadb
- memcached
- rabbitmq

Change-Id: I2aba745a6e3928c52642f64551470fd08cbfd058
Partial-Implements: blueprint ansible-specific-task-become