Tor ignores tunneled connections when checking existing directory downloads

Tor tries to avoid multiple connections to the same directory server to avoid overloading it.

But when checking for existing directory downloads from a server in router_pick_trusteddirserver_impl and router_pick_directory_server_impl, tor ignores connections made via a one-hop ORPort tunnel, and connections made via tor.

This is a hard problem to solve, because ORPort connections can be used for multiple purposes, and can be indirect, so we can't just check the address and port like the existing code does.