Created by: shanyi15

1. 【fixed】protobuf typo http://paddlepaddle.org/documentation/docs/zh/1.3/advanced_usage/design_idea/fluid_design_idea.html

2. 【fixed】文档表述优化 http://paddlepaddle.org/documentation/docs/zh/1.3/beginners_guide/programming_guide/programming_guide.html

3. 文档表述优化 @sneaxiy Please take a look http://paddlepaddle.org/documentation/docs/zh/1.3/user_guides/howto/prepare_data/use_py_reader.html

4. 【fixed】typo：DistributeTranspiler

5. 【fixed】 typo

6. 文档bug【修改了出现同类问题的4篇文档】 https://github.com/PaddlePaddle/Paddle/issues/16567#issue-427250364

7. typo @kuke

8. API使用指南->API快速检索[done]

9. 更换book repo中下图的地址