Quota plugin cephfs

[at88mph]

Minor cleanup
Added quota plugin implementation for CephFS
Yet untested, but here for draft review

[pdowler]

looks like you need to install the ubuntu attr tools in the CI build. will also need to add them to the cavern Dockerfile (in fedora it is the attr package)

while in there, it would be good to update to java 11.

[pdowler]

This looks good. Will aim for a release early next week.

one cosmetic change.

The error handling in the cavern PutAction is hard to evaluate and I don't know off hand how vcp will handle that exception (http 4xx code)... probably need to try it out manually

[at88mph]

OK, I will test vcp today. The Checkstyle changes are complete.

[at88mph]

I also had an interesting case where I reset my ceph.quota.max_bytes to something smaller to test the quota writes, but I neglected to reset the user namespace quota. When the Node loaded, it had the user namespace quota value in the NodeProperty, and wouldn't reset to the QuotaPlugin's value, hence the removal of the old value on line 548 of NodeUtil.

[pdowler]

setting the plain quota prop in user space was a mistake (users could modify it) from previous code; we should probably manually look for and remove that user prop. the workaround is OK for now