(svn r1718) Use the enum TileType as parameter/return type for [GS]etTileType() instead of plain int.

This makes it necessary to rename TileType() to GetTileType() because a type and a function may not share the same name.

road_cmd.c

@@ -26,7 +26,7 @@ static bool HasTileRoadAt(uint tile, int i)
 	int mask;
 	byte b;
 
-	switch (TileType(tile)) {
+	switch (GetTileType(tile)) {
 	case MP_STREET:
 		b = _map5[tile];