Merge tag 'v4.8.17' into zygo-4.8.x-zb64

This is the 4.8.17 stable release

# gpg: Signature made Mon Jan  9 02:22:47 2017 EST using RSA key ID 6092693E
# gpg: Can't check signature: public key not found

diff --cc fs/btrfs/disk-io.c
Simple merge

diff --cc fs/btrfs/extent-tree.c
Simple merge

diff --cc fs/btrfs/relocation.c
Simple merge