`AverageMeter` is not correct in `test.py`

[dreamerlin]

AverageMeter in TIN/utils.py which is used in test.py is not correct.

The AverageMeter in this file only calculates the acc with the history list, which is with self.length long. So the final ouput is not right. It can be reproduced by changing the batch size of the test, the acc will also change, which is abnormal.

I think it should use AverageMeter in this.

[deepcs233]

Have fixed it in the latest version