fix build error, add c# wrapper class

Tino Hager

2018-06-24 b2c03b1615535dc717e196c560901e9e420c96d6

 src/cost_layer.h

@@ -1,7 +1,7 @@
#ifndef COST_LAYER_H
#define COST_LAYER_H
#include "params.h"
#include "layer.h"
#include "network.h"

typedef layer cost_layer;