Reviewer: Andy: Script the creation of an AMI

Changes are to
- anonymise a system prior to creating the AMI
- actually create said AMI automatically (create an AIO, anonymise it, stop it, create AMI from it & terminate it).
There are also changes to stop commands like "knife deployment resize" from killing AIO/AMI nodes created under the same environment.

AMI creation tested extensively. AMIs have had live suite & manual calls made through them. Regular chef deployments have been regression tested (live suite & manual calls).

NB There is one related change in clearwater-infrastructure