Upgrade puppetlabs/apt to 1.4.2

https://github.com/puppetlabs/puppetlabs-apt/compare/1.4.0...1.4.2

Mainly there is a bug in the sources.list.erb file which prevents us
adding a new repo.
Prevent puppet autoloading from any installed gem.

This has been done in govuk puppet - the reasoning as follows -

Motivation: this 'feature' causes massive slowdowns.  Disabling it
reduces the runtime on my dev vm from around 1300s to around 60s.

This 'feature' causes puppet to load extensions from any gem that happens
to be installed and provides puppet extensions.  This means that it
repeatedly searches inside every installed gem for any puppet
extensions.  Therefore puppet gets slower the more gems you have
installed.

See http://projects.puppetlabs.com/issues/7788 for details on this
'feature'.
Add azul::repo

We would like to try out Zulu OpenJDK 8. This is a first step towards
that.
Merge pull request #526 from alphagov/feature/azul-repo

Add Azul apt repo
Merge pull request #527 from alphagov/add-govuk-performance-monkey-patch

Prevent puppet autoloading from any installed gem.
Upgrade ruby version for building the dev VM

gds-boxen [1] no longer includes that version. 2.0.0 works for the version
of puppet that we use [2].

[1] https://github.com/boxen/puppet-ruby/tree/master/files/definitions
[2] https://docs.puppetlabs.com/guides/platforms.html#ruby-versions
Add Nginx status to collectd on app machines

This adds connection stats from nginx into graphite.

See:
https://collectd.org/wiki/index.php/Plugin:nginx
http://wiki.nginx.org/HttpStubStatusModule
Add backend nginx logs to logstash

I have no idea how this wasn't happening.
Merge pull request #530 from alphagov/backend-nginx-to-logstash

Add backend nginx logs to logstash
Rearrange nginx modules to reduce hiera duplication
Merge pull request #529 from alphagov/add-nginx-status

Add nginx status
Merge pull request #528 from alphagov/bump-ruby-version

Upgrade ruby version
Fix nginx import on non app roles

App servers are not the only servers with nginx.
Merge pull request #531 from alphagov/fix-nginx-includes

Fix nginx import on non app roles
Allow redis from frontend machines

Redis sessions required by admin app which is hosted on frontend
machines, not backend machines.
Merge pull request #532 from alphagov/allow-redis-from-frontend

Allow redis from frontend machines
collectd::plugin::nginx is a class not a defined type
Merge pull request #533 from alphagov/fix-nginx-includes

collectd::plugin::nginx is a class not a defined type
Revert ruby version to 1.9.3

This means that the puppet artefact is built with ruby 2.0.0 gems, which
causes deploy to fail.
Merge pull request #534 from alphagov/revert-rbenv

Revert ruby version to 1.9.3