2 - When any country code is listed in ExcludeNodes or
3 ExcludeExitNodes, and we have GeoIP information, also exclude
4 all nodes with unknown countries ({??} and {A1} if
5 present). This behavior is controlled by the new
6 GeoIPExcludeUnknown option: you can make such nodes always
7 excluded with 'GeoIPExcludeUnknown 1', and disable the feature
8 with 'GeoIPExcludeUnknown 0'. Setting 'GeoIPExcludeUnknown auto'
9 gets you the default behavior. Implements feature 7706.