Minor changes to documentation
Minor documentation update for select plugin
Add comments to describe function arguments
Correction to error returned by step request error for too many CPUs

If step requests more CPUs than possible in specified node count of job
allocation then return ESLURM_TOO_MANY_REQUESTED_CPUS rather than
ESLURM_NODES_BUSY and retrying.
Improve error checking for step allocation with min and max node count
Merge branch 'slurm-2.5'

Conflicts:
	doc/man/man1/sbatch.1