Revert geoip db to May 2012
In Tor 0.2.3.17-beta we moved to the June maxmind db. It is becoming anti-helpful (#6266 (moved)). In particular, Karsten says the June db is way worse than the May db.
The longer-term solution starts with #6318 (moved).
The shorter-term solution is to revert to the May db, and stop updating until we have a solution.