while testing for termination.

The slurmd build no longer includes mgr.c, task.c, slurmd_job.c, io.c,
fname.c, ulimits.c, and pdebug.c since these are only needed in the new
slurmd_step binary.

Both slurmd and slurmd_step daemons now include slurmd_step_init.c which
has the pack/unpack functions used at slurmd_step startup time.

The run_script function is moved to its own file run_script.c since both
daemons need it at the moment.  This is candidate for moving to src/common.

Broke slurmd_step.c up into functions in preparation for future code
additions.

read_proc.c does not appear to be used anywhere, so that might
be another file that could be removed from the slurmd build.

 first one arrived  when first terminate was being processed).
Check if a job's credential has been revoked before launching 
 additional tasks.

and restructure some code to comply with linux kernel programming standard.

with a DRAIN flag. COMPLETING state is changed to a COMPLETING flag.