Support Z coordinate in geometry classes

[Kirill888]

shapely and pyproj can operate on geometries/coordinates with XYZ coordinates, not just XY. odc-geo currently assumes that geometries have XY coordinates only. This should change to match capabilities of the underlying libraries.

It is required for an upcoming point cloud support.

At the very least we need to support

• Creating points with 3d coords present (odc.geo.point, odc.geo.multipoint)
• Geometry.to_crs(..) should work with XYZ geometries

since underlying libs support it already, the only concern I have is with type annotations, those will have to change and possibly have complicated "overload" functionalities defined.