Use LatLng from latlong2 instead of LngLat

[JFtechOfficial]

the latlong2 package is widely used for latitude-longitude representation. It offers a fromJson method and it's well maintained. This would allow inter compatibility with other packages like flutter_map.

[liodali]

sorry for late reply, yeah in general what we have in current already done in that package for now we dont have plan to integrated in our package but maybe in the future