Clusters dashboard

Totally work in progress, but at least applies now (after lying dormant for 3 months). Not sure if it even works, to be confirmed... I also need to do a massive rebase to make sure it looks like I know what I'm doing. Use at your own risk.


I'm totally for not hard coding the 'nova-multi-compute' string here, but I'm not sure what you mean exactly. A separate module, or config file? ```catalog.yml``` does not hold such info, IIUC.