frontend: Various fixes
openid_provider: Disable SELinux and enable persistant Journal

Default SELinux policy seems to prevent the uWSGI process from reading
stuff in /srv and raises a bunch of errors for Cherokee trying to
connect() to its socket, too. It'd be possible to fix this but I'd
rather not bother, and since we don't use SELinux in Baserock it's not
super important anyway.

If you did want to fix this I'd suggest installing 'setroubleshoot' and
reading <https://fedoraproject.org/wiki/SELinux_FAQ> as a starting
point.
openid_provider: Update Packer template for new DataCentred cloud

Includes some fixes for the fact that we need to SSH in as 'fedora'
user, not 'root'.
frontend: Enable logging for HAProxy

Note that by default the systemd journal doesn't have any limit on the
amount of disk space it uses, and this system uses the default
configuration so it will eventually fill its own disk up with logs.

Switching to Ansible for provisioning this system should make it easier
to fix this.
Try to work around corrupted OpenStack images in a different way

I continue to find that the OpenStack images deployed by Packer are
often corrupt, in that files added during provisioning exist but are
truncated to 0 bytes.

I found <https://github.com/mitchellh/packer/issues/1462> which suggests
the problem might be that Packer takes a snapshot without shutting down
or even running 'sync' in the image. Adding lots of 'sync' calls at the
end of provisioning does seem to have helped, so far!
openid_provider: Fix URL in index template -- it should be openid.baserock.org
Work around a Packer bug when deploying development images

Issue is: <https://github.com/mitchellh/packer/issues/1656>. The problem
only exists in Red Hat-based operating systems, because for some reason
'cp' gets aliased to 'cp -i', and for some reason Packer doesn't clean
up the temporary shell scripts it creates in the system or use 'cp -f'
to overwrite them.

As a workaround, use '/bin/sh' instead of '/bin/bash' as the shell for
Docker deployments, which I think is an improvement in general because
the less clever shell code involved in deploying a system the better.