Please upadate codes for latest version of PyTorch

[LT1st]

In file train.py and train_search.py, you need to replace this:

    # objs.update(loss.data[0], n)
    # top1.update(prec1.data[0], n)
    # top5.update(prec5.data[0], n)

to

    objs.update(loss.item(), n)
    top1.update(prec1.item(), n)
    top5.update(prec5.item(), n)