Continuation of 1252d1a1
Bug 1938

Requeue/hold batch job launch request if job already running. This is
  possible if node went to DOWN state, but jobs remained active.
In addition, if a prolog/epilog failed DRAIN the node rather than
  setting it down, which could kill jobs that could continue to
  run.
bug 1985

Previous logic would not report termiation siganl, only exit code,
  which could be meaningless.

Bug 1938

Bug 1984

When nodes have been allocated to a job and then released by the
  job while resizing, this patch prevents the nodes from continuing
  to appear allocated and unavailable to other jobs. Requires
  exclusive node allocation to trigger. This prevents the previously
  reported failure, but a proper fix will be quite complex and
  delayed to the next major release of Slurm (v 16.05).
bug 1851

The 2 came from the nodelist being "None assigned", which would be treated
as 2 hosts when sent into hostlist.

If user belongs to a group which has split entries in /etc/group
    search for its username in all groups.
Ammendment to commit 93ead71a
bug 1738

Correct counting for job array limits, job count limit underflow possible
    when master cancellation of master job record.
bug 1952

Also a very minor sanity check in job_mgr.c to make sure we at least have
a task count.  This shouldn't matter, but just to be as robust as possible.

only 1 job was accounted (against MaxSubmitJob) for when an array was
submitted.

This prevents a step from being launched if the job is killed
while the prolog is running. Reproducing the original failure
requires use of srun to trigger the prolog and using scancel
while that prolog is running.
bug 1755

And add missing documenation.
Bug 1921

GRES were not being properly tracks for multiple simultaneous steps.
A step which could have run later could be rejected as never being
able to run.
Replacement for commit dd842d79, which was reverted in commit 6f73812875c
bug 1925

That commit would address a limited subset of problems and introduce
other bugs rather than fixing the root of the problem.

and you use all the GRES up instead of reporting the configuration isn't
available you hold the requesting step until the GRES is available.

Don't trucate task ID information in "squeue --array/-r" output.
Task ID info in sview also expanded to 64 characters (from ~16 chars).

At the start of a scheduling cycle, the job's "reason" field can
be cleared. If the scheduler fails to reach that job and set its
value to a new reason, the original reason was lost and the state
reports would report NoReason. This change saves the last reason
for a job being in a pending state and reports that value to the
user until we have a new valid reason for it still being in a
PENDING state.
bug 1919

bug 1920

Do not use full path for true utility in testsuite. Its location
differ across systems (/bin/true on Linux and /usr/bin/true on BSD).

Previous logic would set the avail_node_bitmap when
a node was powered down, even if the initial state was
DOWN or DRAINED. This made the node available for allocation
to a job, which we don't want until the DOWN or DRAIN
state is cleared.
bug 1893

This reverts commits
7660da9e
5c386455 and
f6c5302b

Bug 1741