Merge branch 'save_ext' into jgrpp

# Conflicts:
#	config.lib
#	src/misc_gui.cpp
#	src/network/network_gui.cpp
#	src/settings_type.h
#	src/smallmap_gui.cpp
#	src/smallmap_gui.h
#	src/station_cmd.cpp
#	src/toolbar_gui.cpp
#	src/vehicle_gui.cpp
#	src/window.cpp

src/town_cmd.cpp

@@ -3622,7 +3622,7 @@ Town *ClosestTownFromTile(TileIndex tile, uint threshold)
 			if (!HasTownOwnedRoad(tile)) {
 				TownID tid = GetTownIndex(tile);
 
-				if (tid == (TownID)INVALID_TOWN) {
+				if (tid == INVALID_TOWN) {
 					/* in the case we are generating "many random towns", this value may be INVALID_TOWN */
 					if (_generating_world) return CalcClosestTownFromTile(tile, threshold);
 					assert(Town::GetNumItems() == 0);