add macro definition to inject serialization of arma cube
add macro definition to inject serialization of arma cube

ranjan1990/mlpack,ranjan1990/mlpack,ajjl/mlpack,darcyliu/mlpack,darcyliu/mlpack,ajjl/mlpack,palashahuja/mlpack,palashahuja/mlpack,ajjl/mlpack,palashahuja/mlpack,ranjan1990/mlpack,darcyliu/mlpack