Refactor scancel so that all pending jobs are cancelled before starting
cancellation of running jobs. Otherwise they happen in parallel and the
pending jobs can be scheduled on resources as the running jobs are being
cancelled.

Expect doesn't seem to be reading the full buffer, so the test
was modified to pass. Expect is only looking at the first 100
lines of ouptut from "sbatch --help".

Minor revisiions to the logic and documentation of commit
26624602

Add SchedulerParameters option of sched_min_interval that controls the
minimum time interval between any job scheduling action. The default value
is zero (disabled).
bug 1623

Initialize some variables used with the srun --no-alloc option that may
cause random failures.

job.  This is already handled on the stepd when the script finishes.

often an inventory request is handled.

free afterwards would not have zeroed out memory on the variables that
didn't get unpacked.

sbatch to stop parsing script for "#SBATCH" directives after first command.
It keeps parsing so long as lines contain only white space or comments
(first non-white space character is '#').

bug 1608

Add SchedulerParameters option of "sched_max_job_start="  to limit the
number of jobs that can be started in any single execution of the main
scheduling logic.

Bug 1601

Bug 1603

and update NEWS

the same time, don't double bill the down time.

Also make the man page headers and footers consistent.
bug 1308