New API stuff to check

LuaTrain::get_rails()
LuaTrain::go_to_station()
LuaTrain::path
LuaTrain::max_forward_speed and max_backward_speed
on_train_schedule_changed event
LuaEntity::get_train_stop_trains()
LuaGameScript::get_train_stops(), LuaSurface::get_train_stops(), and LuaForce::get_train_stops()
LuaGameScript::tick_paused and ticks_to_run read/write (debugging?)