Subprogram global_class::common_weak_rates: Move the following to tw_rate_module
Subprogram mergesort_module::rrate_sort (num, rate_array): Expand and change this subroutine
Subprogram network_init_module::switch_evolution_mode (init): At this point it could be useful to check here the difference between the saved value of dYdt from the network and the dYdt calculated by the nse abchange function, right after the network->nse switch