Supply dashboards from appliance repo (& fix dashboard typos) (#168)

* Add openhpc-slurm dashboard rev2 ..

https://grafana.com/grafana/dashboards/13426/

* Add slurm-jobs dashboard at rev 1 ...

https://grafana.com/grafana/dashboards/13535/revisions

* fix dashboard typos

* enable grafana dashboards to be provided in-role

Author: sjpb