volume events

[rob-baron]

either fix or remove volume event from xdmod-openstack (moc_xdmod_openstack_reporting.py).

Although the generic and the openstack structure has structures to pass mounted drive information to xdmod, this is not as useful as it first seems. Currently, this ignores the drives that were allocated, but not mounted and with our method of collecting data, we could possibly miss when certain drives are mounted.

It is much more useful to report on all allocated drives by configuring storage metrics and writing a different process to gather and format the information. (see #87)