optimize.hpp: reduce space for class_cexp_pair objects.
optimize.hpp: reduce space for class_cexp_pair objects.

kaskr/CppAD,wegamekinglc/CppAD,wegamekinglc/CppAD,wegamekinglc/CppAD,wegamekinglc/CppAD,wegamekinglc/CppAD,kaskr/CppAD,kaskr/CppAD,kaskr/CppAD,kaskr/CppAD