LU-5657 man: manpages for Lustre HSM user API

LU-5657 man: manpages for Lustre HSM user API

Added 2 man pages describing the following HSM user API functions:

  llapi_hsm_action_begin
  llapi_hsm_action_end
  llapi_hsm_action_get_dfid
  llapi_hsm_action_get_fd
  llapi_hsm_action_progress
  llapi_hsm_copytool_get_fd
  llapi_hsm_copytool_recv
  llapi_hsm_copytool_register
  llapi_hsm_copytool_unregister

Change-Id: Icd9c738c7b5287b5cfac2db4b697acb5a9e758ba
Signed-off-by: frank zago <fzago@cray.com>
Reviewed-on: http://review.whamcloud.com/12061
Reviewed-by: Henri Doreau <henri.doreau@cea.fr>
Tested-by: Jenkins
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>