on test failure, abort instead of exit, so we can get a stack trace
on test failure, abort instead of exit, so we can get a stack trace

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