Using geolite2, we attempt to detect the continent of the server
and store the 'continent code' in the serverlist. This is reasonably
broad enough to help players in the client find truly "nearby" server.
The client will have to be changed to select a continent to change
ordering or filtering.
This is a standard way of indicating requirements for
Python projects, since it makes it easy to automatically
install all needed packages with the correct versions.
