cloud sql replicas and passwords

cmd/cgat/main.go

lib/gat/modules/cloud_sql_discovery/config.go

lib/gat/modules/cloud_sql_discovery/discoverer.go

lib/gat/modules/digitalocean_discovery/discoverer.go

lib/gat/modules/discovery/module.go

lib/gat/modules/ssl_endpoint/module.go

lib/gat/pool/pool.go