[Sheepdog] support object recovery

[Piavlo]

I've created an image with the new code with copies=2 on 3 nodes
one node got 554 object allocated on it for the image other 350 and
third just 116
now 350+116 < 554
so it looks like there is no 2 copies redundancy

Alex


MORITA Kazutaka wrote:
> Hi all,
>
> I've updated the next branch.
>
> git://sheepdog.git.sourceforge.net/gitroot/sheepdog/sheepdog next
>
> Object recovery is partially supported.
> If multiple nodes are down sequentially, object recovery wouldn't work.
> But otherwise, lost object should be recovered correctly.
>
> Thanks.
>
>