New feature: warning when project has few cpu hours left.

When submitting jobs, if the project has less than 10 % left of its cpu hour quota, sbatch/salloc will now print a warning. Hopefully this will help projects avoid running out of quota.

It is possible to disable the warning, if needed, by setting the environment variable SLURM_SUBMIT_SUPPRESS_QUOTA_WARNING to 1 in your shell (for instance in one of the Bash startup files). It is also possible to disable all warnings we add when submitting jobs by setting SLURM_SUBMIT_SUPPRESS_WARNINGS to 1 . (Currently, we have only implemented the quota warning.)