As soon as we have received the SSLRequest packet, and have figured
out the hostname to connect to from the SNI, we can start passing
through data. We don't need to parse the StartupPacket that the client
will send next.
In order to not to create NodePorts for each compute we can setup
services that accept connections on wildcard domains and then use
information from domain name to route connection to some internal
service. There are ready solutions for HTTPS and TLS connections
but postgresql protocol uses opportunistic TLS and we haven't found
any ready solutions.
This patch introduces `pg_sni_router` which routes connections to
`aaa--bbb--123.external.domain` to `aaa.bbb.123.internal.domain`.
In the long run we can avoid console -> compute psql communications,
but now this router seems to be the easier way forward.
