net/ceph-devel: update wip.v2017-05-01 -> wip.v2017-07-27-1

• roughly equal to 12.1.2 Luminous RC2
• Major diffrence is that it also incluse the code for rbd-ggate, which allows to mount ceph-pools as raw device. (/dev/ggate)
• ceph-fuse is working, albeit slow and typical fuse style.

Submitted by: Willem Jan Withagen <wjw@digiware.nl> (maintainer)
Relnotes: http://ceph.com/releases/v12-1-2-luminous-rc-released/
Differential Revision: https://reviews.freebsd.org/D11770