* BC breaks:
- The option smpi/async_small_thres was renamed to smpi/async_small_thresh
as we attempt to unify our naming schemes -> smpi/send_is_detached_thresh
* BC breaks:
- The option smpi/async_small_thres was renamed to smpi/async_small_thresh
as we attempt to unify our naming schemes -> smpi/send_is_detached_thresh