Make private_nets aware of Carrier Grade NAT (RFC 6598)
In #28525 (moved), we make tor_addr_is_internal_()
aware of RFC 6598. teor has said that we need a consensus method to do this in private_nets
:
It is important
* that all authorities agree on that list when creating summaries, so don't
* just change this without a proper migration plan and a proposal and stuff.