This change ensures commands run in the kolla-ansible container are done
as the 'ansible' user rather than root.
By default Ansible tries to write it's temporary files to $HOME/.ansible
on the target, which in most cases won't exist when run as the new user.
Hence we now supply the kolla-ansible container with an ansible.cfg, to
tweak the remote_dir option to /tmp.
Change-Id: I838a8c8cd0c7dc1aeca4d12e38c346f252170e7c
Partially-Implements: blueprint drop-root
0f315a0ed0