Create integration testing framework for networks of services

[cortadocodes]

We need an integration test framework that allows us to roll out changes to networks of inter-dependent services with an obvious and clear cut procedure that we can use to find any problems without messing up the production network of services.

We'd also like to capture edge cases by doing things like rolling out to different services in different orders etc.

[thclark]

Whilst looking here for an unrelated resource to test terraform, it took me to kitchen-terraform which might be a good candidate for helping with this. Not sure yet but worth educating ourselves.

[cortadocodes]

This looks great