Function lonlat_bng::convert_to_lonlat_threaded_vec

pub fn convert_to_lonlat_threaded_vec<'a>(eastings: &'a mut [f64],
                                          northings: &'a mut [f64])
                                          -> (&'a mut [f64], &'a mut [f64])

A threaded wrapper for lonlat_bng::convert_osgb36_to_ll