message: add doxygen for write_profiling
diff: #include <vector>
  namespace cmdstan {
  +
  +/**
  + * Writes the data from the map of profiles in a CSV format
  + * to the supplied writer.
  + *
  + * @param writer object of a Stan writer class to write to.
  + * @param p reference to the map of profiles
  + */
  void write_profiling(stan::callbacks::writer& writer,
  stan::math::profile_map& p) {
  stan::math::profile_map::iterator it;
  @@ -17,31 +25,22 @@ void write_profiling(stan::callbacks::writer& writer,
  << std::endl;
  for (it = p.begin(); it != p.end(); it++) {
  profile_csv_stream
  - // name
  << it->first.first
  << ","
  - // thread_id
  << it->first.second
  - << "," //
  - // time_total
  + << ","
  << (it->second.get_fwd_time() + it->second.get_rev_time())
  << ","
  - // forward_time
  << it->second.get_fwd_time()
  << ","
  - // reverse_time
  << it->second.get_rev_time()
  << ","
  - // chain_stack_total
  << it->second.get_chain_stack_used()
  << ","
  - // nochain_stack_total
  << it->second.get_nochain_stack_used()
  << ","
  - // autodiff_passes
  << it->second.get_num_rev_passes()
  << ","
  - // no_autodiff_passes
  << it->second.get_num_no_AD_fwd_passes() << std::endl;
  }
  writer(profile_csv_stream.str());
  