message: Update README.md with docker image.
diff: @@ -30,6 +30,16 @@ A binary build of ONNX is available from [Conda](https://conda.io):
  conda install -c ezyang onnx
  ```
  +## Docker
  +
  +A docker image with ONNX, PyTorch, and Caffe2 is availiable for quickly trying [tutorials that use ONNX](http://pytorch.org/tutorials/advanced/super_resolution_with_caffe2.html). Simply run:
  +
  +```
  +docker run -i -t houseroad/onnx-docker /bin/bash
  +```
  +
  +Currently the image only supports CPU computation with GPU support coming soon.
  +
  ## Source
  You will need an install of protobuf and numpy to build ONNX. One easy
  