message: Updated README.md for v1.8.0
diff: @@ -27,40 +27,10 @@ Intel Extension for PyTorch is a Python package to extend official PyTorch. It i
  |[v1.0.1](https://github.com/intel/intel-extension-for-pytorch/tree/v1.0.1)|[v1.5.0-rc3](https://github.com/pytorch/pytorch/tree/v1.5.0-rc3 "v1.5.0-rc3")|
  |[v1.0.0](https://github.com/intel/intel-extension-for-pytorch/tree/v1.0.0)|[v1.5.0-rc3](https://github.com/pytorch/pytorch/tree/v1.5.0-rc3 "v1.5.0-rc3")|
  - Take Intel-Extension-for-Pytorch v1.8.0 as the example.
  +For IPEX version earlier than 1.8.0, a patch has to be manually applied to PyTorch source code. Please check previous installation guide.
  - 1. Install PyTorch from binary
  - ```bash
  - conda install pytorch torchvision torchaudio cpuonly -c pytorch
  - ```
  -
  - 2. Install PyTorch from source
  -
  - Get PyTorch v1.8.0 source(Refer to [PyTorch guide](https://github.com/pytorch/pytorch#get-the-pytorch-source) for more details)
  - ```bash
  - git clone --recursive https://github.com/pytorch/pytorch
  - ```
  -
  - Checkout PyTorch to the specified version
  - ```bash
  - cd pytorch
  - git checkout v1.8.0
  - ```
  -
  - Update submodules
  - ```bash
  - git submodule sync
  - git submodule update --init --recursive
  - ```
  -
  - Build and install PyTorch (Refer to [PyTorch guide](https://github.com/pytorch/pytorch#install-pytorch) for more details)
  - ```bash
  - python setup.py install
  - ```
  +From IPEX 1.8.0, compiling PyTorch from source is not required. If you still want to compile PyTorch, please follow instructions [here](https://github.com/pytorch/pytorch#installation). Please make sure to checkout the correct PyTorch version according to the table above.
  -### Install Intel Extension for PyTorch from Source
  -
  -Get the source code of Intel Extension for PyTorch
  ```bash
  git clone --recursive https://github.com/intel/intel-extension-for-pytorch
  cd intel-extension-for-pytorch
  @@ -68,16 +38,8 @@ cd intel-extension-for-pytorch
  # if you are updating an existing checkout
  git submodule sync
  git submodule update --init --recursive
  -```
  -
  -Install dependencies
  -```bash
  -pip install lark-parser hypothesis
  -```
  -Install the extension
  -```bash
  -cd ${intel_extension_for_pytorch_directory}
  +# run setup.py to compile IPEX and install the binaries
  python setup.py install
  ```
  