[Sheepdog] rebased client tree onto qemu.git v0.12.4

[MORITA Kazutaka]

Hi all,

I have rebased the client tree onto qemu.git to prepare for posting
sheepdog patch to the qemu community.

    git://sheepdog.git.sourceforge.net/gitroot/sheepdog/qemu

There is another branch `live-migration' in the tree.  This includes a
patch to support block driver claim and release hooks (written by
Chris Webb).  I'll push the disk lock features to the qemu community,
too.  But at this time, I think of pushing only the sheepdog client
block driver patch to make the patch simpler.

The previous tree (qemu-kvm.git) is deprecated though I'll maintain it
for a while.

Thanks,

Kazutaka