- Bugzilla 214: Have LOV do its own timeout management, so that all OSCs get

- Bugzilla 214: Have LOV do its own timeout management, so that all OSCs get
  removed correctly, _and_ we don't crash as soon as we try to kick off
  recovery.  What a deal!

- Fix removal of OSC from LOV on OST failure (silly & and type-smashing
  list_head macros).

- Lots of comments in lov_brw, so I don't have to figure it out from first
  principles next time.  (I think they're correct, but Andreas will review to
  make sure.)

- Skip inactive OSCs in lov_statfs, because otherwise we return -EIO and
  the caller will ignore all of the data we get from the active/working OSCs.

- A bit more bulletproofing of the sync_io_timeout case -- if you see that
  message, please reopen the bug.

- Be a little smarter about double-failed connections.  Might make
  failure-in-recovery work better, and will definitely make multiply-detected
  connection failure work better.