Verifies whether elevation mode is correct.
See also
Other setting functions:
reverse_back_if_direct_mode(),
reverse_if_direct_mode(),
set_breakdown(),
set_cutoffs(),
set_expanded_travel_times(),
set_fare_cutoffs(),
set_fare_structure(),
set_max_fare(),
set_max_lts(),
set_max_rides(),
set_monte_carlo_draws(),
set_n_threads(),
set_new_congestion(),
set_new_lts(),
set_output_dir(),
set_percentiles(),
set_progress(),
set_speed(),
set_suboptimal_minutes(),
set_time_window(),
set_verbose()