[OOTB-infra] ssh pubkeys

[Martin Cosgrave]

Foreman/puppet can manage the ssh keys and users for each machine in its 
control, so what I can do is create a puppet manifest with authorised 
users' usernames and keys in, and apply that to the configuration of 
every machine. This means that puppet will constantly keep the 
authorized_keys updated and if we want to remove a key from all servers 
we can do so very easily from a single configuration.

Therefore if you would like to send me your public ssh keys, please do 
so. I will add you as a user to the manifest along with your keys, so 
you should be able to log on to all puppet-managed machines

We can selectively apply the keys on a per-machine basis, for example we 
may define flags such as 'allow_devs' 'allow_testers' etc. and apply 
them differently to each machine.