Add new scontrol command "ping", report up slurmctld daemons when getting config.

job_cancel arrives. job/step complete RPCs will now return job completed
error, but the immediate turn-around is required for DPCS.

Report unset task_dist value as -1 instead of 49151
(NOVAL) in job request log.

addition to the user id (used to just print user id).

 o src/slurmd : do not bother to sleep full timeout in rpc_timelimit
   if the job step goes away on SIGTERM.
 o src/common/slurm_auth.c : get default plugin dir from SLURM_PLUGIN_DIR
   rather that always "/usr/local/lib/slurm"
 o other small fixes

This puts core file in desired location in any case.

   command line as suggested by GNU coding standards

particularly with respect to FAILED or DOWN nodes.

Shutdown any backup controller before restoring state.

   but sysv semaphore doesn't

 o changes to some of the logic in slurm_cred_t validity checks

node registration RPC.

don't need to worry about the backup controller freeing it then trying
to use it again when it takes over a second time.

Minor mods to programmer.guide.html
Added quick.start.guide.html for introduction to the system for new users
and administrators.

Convert arch from tgif/.obj file to dia file for better compatability
and the ability to easily generate a .png file (for html).

Remove vestigial dashed line.