If the environment variable is greater than MAX_ENV_STRLEN don't
set it in the job env otherwise the exec() fails.
Update NEWS file, make a minore format change.
Slow down "lazy" scheduling

Rather than attempting a scheduling loop as frequently as every
1 second, wait 3 seconds for performance reasons.
Optimize scontrol hold/release for job arrays

Cache job information and drop out of loop after finding the
desired array task. This improves performance a fair bit.
bug 684
Merge branch 'slurm-14.03'