libcephfs: fix default parameters document for ceph_open_layout

Signed-off-by: Andras Elso <elso.andras@gmail.com>
client: fix log data

Signed-off-by: Andras Elso <elso.andras@gmail.com>
client: use get_filehandle

Signed-off-by: Andras Elso <elso.andras@gmail.com>
client: allow change file owner or group only

Signed-off-by: Andras Elso <elso.andras@gmail.com>
client: add some new functions: lchmod, fsetattr, lutime

Signed-off-by: Andras Elso <elso.andras@gmail.com>
Merge pull request #78 from Elbandi/master

Some fixes and functions for libcephfs and client

Reviewed-by: Sage Weil <sage@inktank.com>