update zmp

Osm/osm_mapnik.zmp/params.txt

@@ -23,4 +23,4 @@ DefHotKey=16463
 BanIfLen=0
 PARENTSUBMENU=OSM
 IteratorSubRectSize=8,8
-RequestHead=User-Agent: SAS.Planet
+RequestHead=Referer: http://www.openstreetmap.org/