Feature request: Kerberos support

[danielhoherd]

Is your feature request related to a problem? Please describe.

No.

Describe the solution you'd like

I'd like the kerberos protocol to be supported.

Describe alternatives you've considered

pgbouncer does not have this feature built in, though there is a thread where they are working on it.

Additional context

For certain enterprise deployments, kerberos is required. Having a connection pooler that can handle kerberos would be a fantastic selling point for pgcat in those environments.