Creating the ATAT database requires a separate connection to one of the
default Postgres databases, like `postgres`. This updates the scripts
and secrets-tool command to handle creating the database. It also
removes database creation from Terraform and updates the documentation.
This changes the configuration of the postgres master username and
password. Instead of committing to source (short term hack), this now
sources those secrets from KeyVault. Those secrets are generated and
populated via secrets-tool.
This adds the start of the identity module but also cleans up a bunch of
things like the LBs. Originally I was managing the LBs, but k8s manages
this for us so I disabled the LBs for now.
