Repair OOM(out of Memory) in StyleGestures

The original repo: https://github.com/simonalexanderson/StyleGestures/

Overall I did three things to advoid OOM

Before traing, I split big training file into small pieces.

You should replace the "/StyleGestures-master/motion/datasets/locomotion.py" with locomotion-new.py

Honestly, it takes a lot of time to acomplish this because the data-transform process of StyleGestures is super-complicated.

You should replace the "/StyleGestures-master/motion/datasets/motion_data.py" with motion_data-new.py

I found some data.copy() is unnecessary， but some is necessary. It depends on whether the data will be reused later. If not, the data.copy() is unnecessary.

Finally, the code can run with about 6GB Memory and less than 12GB GPU Memory