Branch b1_6

b=16566
o=Jonathan Li(jli@cray.com)
i=shadow, bobijam

Description: Upcall on Lustre log has been dumped
Details    : Allow for a user mode script to be called once a Lustre log has
             been dumped. It passes the filename of the dumped log to the
             script, the location of the script can be specified via
             /proc/sys/lnet/debug_log_upcall.