Test runtimes

Windows:
Running test Examples/Image/MNIST/03_ConvBatchNorm (debug gpu) - [OK] 214.39 sec
Running test Examples/Image/MNIST/03_ConvBatchNorm (release gpu) - [OK] 64.81 sec

Linux:
Running test Examples/Image/MNIST/03_ConvBatchNorm (debug gpu) - [OK] 44.82 sec
Running test Examples/Image/MNIST/03_ConvBatchNorm (release gpu) - [OK] 19.90 sec