Add Dockerfile to enable local usage

[chester-leung]

We currently offer a Docker image with necessary dependencies, but the image is quite large (~5GB) and takes a while to download. Consequently, we should also provide a Dockerfile as part of this repo to enable users to build the container much faster locally.

[itewqq]

@chester-leung Hi, any update on this? We somehow need the Dockerfile for some customizations. Thanks!