A very simple addition to complex

From: nbecker_at_[hidden]
Date: 2001-06-07 08:58:26

This seem to be an obvious addition.  It is not present in current
library that is part of gcc, at least.

template<typename T>
ostream& operator<< (ostream& os, const complex<T>& z) {
  os << '(' << real (z) << ',' << imag (z) << ')';
  return os;
}