CentOS8 is no longer supported but CentOS8 Stream is.

Change-Id: I2e3d41aa7f26ae4139e73c7b4ed4e76d1df94eee

This commit upgrades the development Vagrant vm to use
CentOS 8.

This also increases the size of the root disk as the
CentOS 8 cloud image is only 10GB which is not
sufficient for a Kayobe deployment.

Change-Id: I614cf6e0a774229da30831e806e2ae125e5cf0fb

This adds the ansible playbooks required by kayobe to the manifest by
using the data_files option in setuptools. When using pip to install
kayobe into a virtualenv, these files will be placed in
<venv>/kayobe/share/.

In an editable install, e.g using `pip install -e .`, data_files are not
installed into the virtualenv. Instead, we must follow the egg-link file
to find out the actual location.

Story: 2004252
Task: 27787
Change-Id: Ibef040eceb547476007f83c0d5dcdb2bc6986d1e

Add a line which states the version of the Vagrant box to be used when
provisioning a development environment.

NB: In this case, 0.2.0 is an image based on CentOS 7.5

Change-Id: I81613df1d20dfd1b99a5d7624fc1627ca185dd7f
Story: 2002086
Task: 19755

The following top level scripts are added under dev/:

* overcloud-deploy.sh
* seed-deploy.sh
* seed-hypervisor-deploy.sh

Some amount of configuration is possible via dev/config.sh.

By default the hostname will be localhost, which causes issues with
RabbitMQ.

This is required in order to allow kayobe to reach the controller prior to
running the network configuration plays.

To avoid a reboot when running the kayobe scripts, we disable selinux
before running the scripts. We do this using the provision reload plugin
that allows us to do a vagrant reload while provisioning the VM.

When doing vagrant halt then vagrant up we want the system to keep
working. The easiest way to do this is to use a virtual box plugin to
install the tools, then use the tools to sync the /vagrant directory,
rather than falling back to rsync on every boot of the VM. The rsync
looses all the writes since the last boot, forcing a full reprovision.

Adds commands to install dependencies, and setup a virtualenv with kayobe
installed. Configuration is provided in dev/ for a single controller with
a single network.