[sheepdog] [ANNOUNCE] sheepdog stable release v0.6.3-rc0

[Hitoshi Mitake]

Hi sheepdog users and developers,

I released v0.6.3-rc0 of stable branch. You can download a source
archive from these URLs:
tar.gz: https://github.com/sheepdog/sheepdog/archive/v0.6.3-rc0.tar.gz
zip: https://github.com/sheepdog/sheepdog/archive/v0.6.3-rc0.zip

The most important updates of this release are:
 - fix memory leak in sockfd cache
 - fix latent segfault in event loop

If no one complains about this release in 2 days, it will be v0.6.3
officialy.

Below is the summary of commits this release contains.

Hitoshi Mitake (2):
      collie: remove a compiler warning
      sheep: correct a way of freeing sockfd_cache_entry

Kai Zhang (1):
      sheep: fixed compile warning

MORITA Kazutaka (2):
      sheep: make invalid_vnode() type safe
      event: refresh event info after unregistering

Thanks,
Hitoshi