LU-2813 hsm: Add user credential information to copy tool RPC

LU-2813 hsm: Add user credential information to copy tool RPC

Add MDT_BODY data to the RPC used for coytool, so the
coordinator can make some check based on the user

Signed-off-by: JC Lafoucriere <jacques-charles.lafoucriere@cea.fr>
Change-Id: Ia45aacfdc78411f7c202bafb6bd6411f686606a6
Reviewed-on: http://review.whamcloud.com/5436
Tested-by: Hudson
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
Tested-by: Maloo <whamcloud.maloo@gmail.com>