- Support multiple lov OBDs per node, by tying the LOV into the same UUID group

- Support multiple lov OBDs per node, by tying the LOV into the same UUID group
  as the OSCs and MDCs.

- The MDS now _always_ creates its own LOV and OSCs/MDC, and there is no longer
  a --mds_ost_conn switch.

- replay-dual should work now, but I haven't tested it.

- the mdc_lock is now per-MDC, and not global

- when a namespace is destroyed, remove the associated lprocfs directory,
  so that it's not there like a landmine with dangling namespace pointers.

- the MDS now knows its LOV by device name (which is lov_$MDSNAME)

- LOV now has an explicit 'descriptor' or 'LOV service' UUID, instead of
  reusing the the device UUID

- print the (possibly useful) mdc name instead of the largely useless and not
  really unique U"U"ID in lprocfs/lov/target_mdc