The OS (tries) to send these but we drop them. No need to worry the
user with spam that we're dropping it.
Fixes#402
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This change adds to tsdns the ability to delegate lookups to upstream nameservers.
This is crucial for setting Magic DNS as the system resolver.
Signed-off-by: Dmytro Shynkevych <dmytro@tailscale.com>