Backfill scheduling fix: If a job can't be started due to a "group" resource
    limit, rather than reserve resources for it when the next job ends, don't
    reserve any resources for it. The problem with the original logic is that
    if a lot of resources are reserved for such pending jobs, then jobs futher
    down the queue may defered when they really can and should be started. An
    ideal solution would track all of the TRES resources through time as jobs
    start and end, but we don't have that logic in the backfill scheduler and
    don't want that extra overhead in the backfill scheduler.
bugs 2326 and 2282

bug 2303

Handle unexpectedly large lines for hostlists. (Bug 2333.)

While here rework to avoid extraneous xstrcat calls by using
xstrfmtcat instead of snprintf + xstrcat. Collapse line end into
own string for readability.

No performance or functional change, aside from removing possible
line truncation (which will silence additional Coverity warnings).

Removes a double xfree() in slurm_sprint_reservation_info().

When a reservation is created or updated, compress user provided node names
    using hostlist functions (e.g. translate user input of "Nodes=tux1,tux2"
    into "Nodes=tux[1-2]").
bug 2333

Match behavior of other PBS-like resource managers. Bug 2330.

Don't allow user specified reservation names to disrupt the normal
    reservation sequeuece numbering scheme.
bug 2318

anything.  The slurmd will process things correctly after the fact.

The restriction from Cray has been lifted.
bug 2317

Otherwise upgrading slurm on a compute node while tasks are running
will cause plugin mismatch, as slurmstepd would not load the library
until task completion before. Bug 2319.

Bug 2314.

this happens anywhere in the code but just incase it ever does, lets fix
it.

This can be caused by a core reservation on nodes which get taken
  out of the system or fail.
bug 2296

salloc/sbatch/srun did not mention this. Also reference OverTimeLimit
as another option affecting the final run time. Bug 2309.

the job starts update the cpus_per_task appropriately.

This also moves update num_tasks to after the setting of node counts on
an update.  It didn't appear to matter, but the cpus_per_task and
pn_min_cpus had to be figured out after the cpus and nodes were set but
before tasks.

Bug 2302

burst_buffer/cray - Improve tracking of allocated resources to handle race
    condition when reading state while buffer allocation is in progress.
Also initialize a mutex

DBD for the first time.  The corruption is only noticed at shutdown.

Bug 2293

Set job's reason to "Priority" when higher priority job in that partition
    (or reservation) can not start rather than leaving the reason set to
    "Resources".
bug 2285

error message.

If a reservation's nodes value is "all" then track the current nodes in the
    system, even if those nodes change. Nodes will automatically be added to
    or removed from a reservation when slurm.conf changes.
bug 2204

Bug 2281

Rename the variable to match rest of codebase while here. This is related to
bug 2295, although snprintf() protects against buffer overflow in 15.08 and up.

Later releases have switched over to snprintf to avoid this issue, but 14.11
did not get that patch. Bug 2295.

time.

static/overlap systems when some hardware issue happens when restarting
the slurmctld.

a dynamic system and mark the block in error on a static/overlap system.

Bug 2273

Don't use lower weight nodes for job allocation when topology/tree used.
bug 2284

Preemption/gang scheduling: If a job is suspended at slurmctld restart or
    reconfiguration time, then leave it suspended rather than resume+suspend.
bug 2274

task/affinity: Disable core-level task binding if more CPUs required than
    available cores.
bug 2267

Log as error if more than 3 aeld connects per second that cause is
  likely duplicate slurmctld daemon
bug 2278

This is needed to properly enforce limits and account for usage.

Remove the 1024-character limit on lines in batch scripts, which was
causing long lines to be silently truncated. I noticed it when jobs were
getting created with fewer dependencies than specified.

Also increase the line length when showing job info.

sched/backfill: If a job can not be started within the configured
    backfill_window, set it's start time to 0 (unknown) rather than the end
    of the backfill_window.
bug 2100