Add geometry for Kosovo with problematic ISO country code

improves openaddresses#3866,
partial alternative solution for openaddresses/machine#700

Author: stefanb

sources/xk/countrywide.json

@@ -4,7 +4,8 @@
             "alpha2": "XK",
             "country": "Kosovo"
         },
-        "country": "Kosovo"
+        "country": "Kosovo",
+        "geometry":{"type":"Polygon","coordinates":[[[20.76216,42.05186],[20.71731,41.84711],[20.59023,41.85541],[20.52295,42.21787],[20.28374,42.32025],[20.0707,42.58863],[20.25758,42.81275],[20.49679,42.88469],[20.63508,43.21671],[20.81448,43.27205],[20.95651,43.13094],[21.143395,43.068685],[21.27421,42.90959],[21.43866,42.86255],[21.63302,42.67717],[21.77505,42.6827],[21.66292,42.43922],[21.54332,42.32025],[21.576636,42.245224],[21.3527,42.2068],[20.76216,42.05186]]]}
     },
     "data": "https://www.dropbox.com/s/3vgtlgkkiadkt7d/xk_addr.csv?dl=1",
     "type": "http",