Add sanity checks to the beginning of the HTTPS bundle

[jviide]

Giving stubs to a host-port pair that usually should verify and some other place that shouldn't would provide some insight whether the stub even works.

Something like www.google.com:443 has been a handy manual sanity check, but on the other hand codifying it would be yet another external dependency.

[jviide]

Ping @oherrala, @Mamietti, @ikisusi, @evilon.

[oherrala]

OpenBSD's NTP daemon checks clock by pinging google.com:443 (see constaints from ntpd.conf).