The previous steps for standing up a new host were somewhat manual.
This further scripts the process, by using the AWS CLI to start the
instance, and pass it a "user data" script to provision itself upon
boot. This results in a hands-off provisioning process which
completes in 5min.
Additional settings are required for `~/.zulip-install-server.conf`.
It is not suited for all roles, as it assumes one instance type and
security group value. Additionally, not all of the post-provision
process is currently automated -- Nagios SSH key verification, for
instance, is still a manual step. There are also additional steps for
database or frontend servers. Regardless, this is a move toward
automated provisioning.
Alex Vandiver