Change names in NEST "RecordablesMap" to name objects

[tclose]

Alongside the main cpp file, create a "names" file that lists the object names using "names" objects. For example the "V_m" names object in the code below

template <> void RecordablesMap<hodgkin_huxley>::create()
{

   insert_("K_m48O", &hodgkin_huxley::get_y_elem_<hodgkin_huxley::State_::K_M48O>);

   insert_("Na_h43O", &hodgkin_huxley::get_y_elem_<hodgkin_huxley::State_::NA_H43O>);

   insert_("Na_m42O", &hodgkin_huxley::get_y_elem_<hodgkin_huxley::State_::NA_M42O>);

   insert_("v", &hodgkin_huxley::get_y_elem_<hodgkin_huxley::State_::V>);


   insert_(names::V_m, &hodgkin_huxley::get_y_elem_<hodgkin_huxley::State_::V>);


}