Created by: wanghaoshuang

The load_parameters API of Paddle1.7 will enforce the shape of weights in scope equals to that loaded from the checkpoint.

https://github.com/PaddlePaddle/Paddle/blame/4e8bc02461826b7b62919e5e9ba0833027b82859/python/paddle/fluid/io.py#L1905

So, it is necessary to prune the scope before loading the checkpoint.

fix #330 (closed)