* Changed Dockerfile
* Update Dockerfile
* Dockerfile
* Update README.md
* Add Dockerfiles
* Update README.md
Removed misleading CUDA version, as the Ubuntu18.04-pytorch1.7.1-cuda11.0-cudnn8 Dockerfile can only support CUDA versions >11.0.
* add a docker file for some users
Ubuntu18.04-pytorch1.7.1-cuda11.0-cudnn8-python3.8
* add a describing file of how to use dockerfile
give some steps to use dockerfile