BLK_SZ added in load.py(default is 8).
np_scheduler.py added, tested.
np_scheduler.py do not compete resources in this version(each procs take resp to BLK_SZ tasks, task size vary with np), because I donot know how to stop msg passing when using while.
usg_pls_ld.py added, tested. comments in np_scheduler.py modified.