Switch between CPU and GPU devices for cnn example
For cifar_distributed_cnn and cnn examples, the model is by default run on the GPU. Need to enable it to run on CPU for machines with only CPUs
Add a conditional judgement to decide whether use CPU or GPU and then apply the devices to datasets and models
https://github.com/apache/singa/commit/0a2d9b20c743b7b1501f1b50db32d36b00de85a0
modify line 114 for judging CPU and GPU in https://github.com/apache/singa/blob/dev/examples/cifar_distributed_cnn/train_cnn.py
This has been resolved in https://github.com/apache/singa/blob/dev/examples/cifar_distributed_cnn/train_cnn.py