Fix copy constructor for StaticTiledMapTile.
Add Polyline contribution from @PrinceManfred
Add PolygonMapObject constructor taking a Polygon
Change PolylineMapObject to use new Polyline class.
Change TmxMapLoader to add y-direction awareness

You can now specify the direction of the y-axis at load time. The map will
be loaded accordingly, inverting objects or tiles as necessary. Thanks to
@PrinceManfred for getting this started.
Add polyline drawing to ShapeRenderer