Fix bug 852: define Traits type in general_matrix_matrix_product when EIGEN_USE_BLAS is defined
Fix bug 852: define Traits type in general_matrix_matrix_product when EIGEN_USE_BLAS is defined

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