This is needed to run a single MPI_COMM_WORLD spread across multiple
  job allocations. The work is incomplete, but well underway in this
  commit (much of the code in place, test suite runs sucessfully).

If the system configuration prevents the tests job from starting,
  terminate the test with a warning.

If submit failed, tried to cancel job ID 0

Systems with less than 3 CPUs per node would fail the test

Logic recently introduced would cancel an entire job allocation if
  a step launch failed, even if the srun command did not create the
  allocation (running under salloc or sbatch).

The srun message changed for pack jobs and the test failed.
  Tweak both message and test for better clarity.

Modify the signal handling and termination functions to operate on
  a list of job steps (pack job) rather than a single record
Add job ID to some srun log messages for pack jobs

Add the pack count argument to slurm_step_launch() function in
  test suite and perl api. The argument was added in commit
  71a34f56

Modify launch/slurm plugin to signal all components of a pack job rather
   than just the one (modify to use a list of step context records).

If prolog is running when attempting to signal a step, then return EAGAIN
   and retry rather than simply returning SLURM_ERROR and aborting.

Fix I/O race condition on step termination for srun launching multiple
   pack job groups. Without this change application output might be
   lost and/or the srun command might hang after some tasks exit.

All of these were pre-existing Coverity errors, but I changed nearby
code, variable names, etc. so they looked like new errors.

Coverity reported problem, CID 45194

CID 44936

Coverity CID 171494

variables

This restores perl API operation after commit aea2f0e2

Bug 3956.

Add translation code for the RPCs as well.

Bug 3956.

Add pack_job_id and pack_job_offset to accounting database.
Modified sacct to accept pack job ID specification using "#+#" notation.
Modified sstat to accept pack job ID specification using "#+#" notation.

NULL is returned if the token is not found, testing against '\0'
is wrong (although does work okay in older compilers).

Fixes new GCC 7.1 warning.

was matching more than expected.

error messages that aren't really errors.

Related to Bug 3997

Without this change, each component would generate separate
  email at job begin, end, etc.

If the pack job allocation partially failed, properly handle accounting
  and deallocation of burst buffer. Note, this should rarely happen.