GL/TLD: TLD-To-Country Service

[clandest]

Build a top-level-domain-to-country-code-group service into the SubstratumNode. This will probably be part data and part code. Make the Node capable of accepting a hostname in its RouteQueryMessage. Put a debug log in the Neighborhood that gives a list of acceptable exit-node countries whenever a route to a hostname is constructed.

Note: this probably shouldn't be an actor.