Cleaned up code that could've caused performance issues when reading config
and there was nodes with features defined.

bug4980

bug 5337

When one asks for an inactive feature and also specifies the node with -w flag,
the node will be rebooted despite it may contain running jobs.

bug4821

and avoid race condition calling task before proctrack can introduce.

Bug 5319

delayed until the first job completes execution and it's burst buffer
stage-out is completed.

Bug 4675

If MailProg is not configured and "/bin/mail" (the default) does
not exist, but "/usr/bin/mail" does exist then use "/usr/bin/mail"
as a default value.

Bug 5159.

Previously the function was only testing against the first partition in
the job_record. Now it detects if the job request is multi partition and
if so then loops through all of them until the job will run in any or
until the end of the list, returning the error code from the last one if
the job won't run in any partition.

Bug 5185

When requesting specific jobids with sacct, the starttime of the request
is 0, which will cause the time range to be outside of the
MaxQueryTimeRange range -- if specified. When requesting specific
jobids, sacct should be able to find the job whenever it started --
unless confined to a smaller range with -S and/or -E.

Bug 5009

For heterogeneous job component with required nodes, explicitly exclude
    those nodes from all other job components.

Specifically due to SELECT ... FOR UPDATE ones.

Bug 5086.

Bug 5270.

Instead of unintentionally rejecting the update from a non-Administrator
if the job_submit plugin modified that field.

Bug 5306.

sched/backfill: Reset job time limit if needed for deadline scheduling.
bug 5183

I do not see a use for this syntax, especially given that it appends
an extra comma in between the two halves. Only allow the full string
to change to put this in line with the Comment handling.

Remove special handling of an identical AdminComment as well,
since the end result is unchanged, and this avoids a potentially
expensive xstrcmp call.

Bug 5306.

Bug 5286

RHEL 6 (and related) use lua as the package name, test
if that package exists with a version >= 5.1 if the other
tests have already failed.

Bug 5263.

bug 4987

And do not list each individual sensor reading but just the computed
sum of each one grouped by key.

Bug5274

This is in anticipation of an upcoming change to the cgroup hierarchy
on a future CLE release.

Bug 5145.

If defined, is called when a node failes to resume by ResumeTimeout.

if any task in the array was requeued. This is a hint to use
"sacct --duplicates" to see the whole picture of the array job.

Bug 5105

burst_buffer.conf - Add SetExecHost flag to enable burst buffer access
    from the login node for interactive jobs.

And remove the initialization before all the calls to the function.

It is non-functional and the motivation is more a preventive thing
so that if we ever use slurm_mktime() we know tm_isdst is consistently
set to -1.

Bug 5230.

which were marked down due to ResumeTimeout.

If a cloud node was marked down due to not responding by ResumeTimeout,
the code inadvertently added the node back to the avail_node_bitmap --
after being cleared by set_node_down_ptr(). The scheduler would then
attempt to allocate the node again, which would cause a loop of hitting
ResumeTimeout and allocating the downed node again.

Bug 5264

Bug 5206.

srun would not return an exit code if a previous task exited before a
latter task exited with a signal.

If multiple tasks exit with a signal, srun returns the highest signal.

Partially reverts commit 04b449e1 -- the setting of local_global_rc
to NO_VAL as srun doesn't need to know whether it's been set or not
anymore. srun always sets the signal if a task exited with a signal.

Bug 5083

There were two code paths building an allocation response by calling
its own static _build_alloc_msg() function:

1. src/slurmctld/proc_req.c
2. src/slurmctld/srun_comm.c

These two functions diverged and both had members that were not filled
in but were filled in the other. This patch makes it so we change the
signature of the one in proc_req.c to make it extern and then in
srun_comm.c we call this newly common function.

Also added cpu_freq_[min|max|gov] members in the common one since these
were the only members missing in proc_req.c function (the one in
srun_comm.c had more members missing, like all the ntasks_per*, account,
qos or resv_name).

Bug 4999.

Only trust MUNGE signed values, unless the RPC was signed by
SlurmUser or root.

CVE-2018-10995.

Do not defer until later, and do not potentially miss out on proper
validation of the user_name field which can lead to improper authentication
handling.

CVE-2018-10995.

Bug 5038.

Caused by pthread_cancel cleanup by commit e5f03971  in 17.11.6.

Bug 5181.

The race condition was created in a7c8964e in 17.11.6 when removing
the (unsafe) pthread_cancel code handling thread termination.

Bug 5164

Commits f18390e8 and eed76f85 modified the stepd so that if the
stepd encountered an unkillable step timeout that the stepd would just
exit the stepd. If the stepd is a batch step then it would reply back
to the controller with a non-zero exit code which will drain the node.
But if an srun allocation/step were to get into the unkillable step
code, the steps wouldn't let the waiting srun or controller know about
the step going away -- leaving a hanging srun and job.

This patch enables the stepd to notify the waiting sruns and the ctld of
the stepd being done and drains the node for srun'ed alloction and/or
steps.

Bug 5164