BookkeeperProtocol.Response.status is completely ignored

As the summary says, if you set the status to anything but ok, it will be ignored by PerChannelBookieClient. If you try to handle it, a whole load of tests fail due to different mapping for read and write requests.

I'm running this while rebasing our auth stuff, which i'll push up when it's been validated. I means the auth stuff needs to be aware of all message types, as I can't just send a EUA error in the packet level status.