Additional Slurm example bindings

[kcgthb]

Provide more Slurm example bindings, to interact with nodes running jobs from specific accounts, or under specific QOSes.

Examples

Generate a folded nodeset from all the nodes running jobs from the myacc Slurm account:

$ cluset -f @slurmaccount:myacc

Count the number nodes running jobs submitted with the long QOS:

$ cluset -f @slurmqos:long