See https://docs.google.com/document/d/1SUSBM9XoTnpaeew0bq4ABmgISc76fjzrY2vapZ10XD4/edit#
Also https://issues.couchbase.com/browse/MB-34277
GOCBC-496 Make auth calls asynchronous
GOCBC-497 Make bootstrap calls asynchronous
GOCBC-498 Add sasl list mechs to boostrap
GOCBC-499 Expose select bucket and implement takeover
GOCBC-505 Add support for cluster level config