Adds 'puppetlabs/apt' module to Puppetfile

Allows for installation of apt such that box can update/upgrade packages.
Allows for introduction of unattended-upgrades in future commit.
Adds 'attachmentgenie/ufw' module to Puppetfile

Allows Puppet to manage installation and updating of ufw module.
ufw rules are controlled in this repo.
Adds 'attachmentgenie/ssh' module to Puppetfile

Allows Puppet to manage installation and updating of SSH package.
SSH package can then be configured elsewhere.
Adds 'blom/rssh' package to Puppetfile

rssh is a restricted shell that only allows rsync to run.
The govuk-backup user has this shell set as its default in user.pp.
This should restrict govuk-backup user to only running rssh.
Adds 'alphagov/lvm' module to Puppetfile

Allows for LVM drives to be created by Puppet.
Used in mounts.pp.
Adds 'alphagov/puppet-ext4mount' module to Puppetfile

Used in mounts.pp to mount ext4 drive.
Adds 'alphagov/puppet-harden' module to Puppetfile

puppet-harden is a module to harden a base installation of Ubuntu.
Details at http://github.com/alphagov/puppet-harden.
Adds 'alphagov/puppet-clamav' module to Puppetfile

Allows Puppet to manage installation and updating of ClamAV.
ClamAV to be configured in clamav.pp manifest.