update address of openstack host, update name of the image with docker on top of ubuntu

create docker image for ubuntu with docker installed

add base image for ubuntu 20.04 LTS

update script for creating base OS images

simplify post-install script by removing extra steps, add separate script for fixing terminal

fix installation script, replace using answers file with custom command

reordered steps of pre-install so its clear that installing software is before configuration of systemd services

update answers.cfg for the new packstack version

update pre-install script to include more handy tools, make the way we add current hostname to /etc/hosts more generic

add new answers file for packstack

change the location of generated certs

enable deletion of images from registry through API

add wait-for script on hosts, move tf files into top directory for easier usage

update due guest.pem key, add terraform directories to gitignore

remove terminal symbols on sourcing OpenStack credentials, add openstack clients to installation