reactivate the sorting in the experimental sparse-sparse product
reactivate the sorting in the experimental sparse-sparse product

mjbshaw/Eigen,mjbshaw/Eigen,rotorliu/eigen,rotorliu/eigen,madlib/eigen_backup,rotorliu/eigen,mjbshaw/Eigen,madlib/eigen_backup,madlib/eigen_backup,madlib/eigen_backup,rotorliu/eigen,mjbshaw/Eigen