message: fix doc for ocr
diff: @@ -18,10 +18,9 @@ tar xf test_imgs.tar
  ## C++ OCR Service
  ### Start Service
  -
  -```
  -#Select a startup mode according to CPU / GPU device
  +Select a startup mode according to CPU / GPU device
  After the -- model parameter, the folder path of multiple model files is passed in to start the prediction service of multiple model concatenation.
  +```
  #for cpu user
  python -m paddle_serving_server.serve --model ocr_det_model ocr_rec_model --port 9293
  #for gpu user
  @@ -29,7 +28,7 @@ python -m paddle_serving_server_gpu.serve --model ocr_det_model ocr_rec_model --
  ```
  ### Client Prediction
  -#The pre-processing and post-processing is in the C + + server part, the image's Base64 encoded string is passed into the C + + server
  +The pre-processing and post-processing is in the C + + server part, the image's Base64 encoded string is passed into the C + + server
  so the value of parameter `feed_var` which is in the file `ocr_det_client/serving_client_conf.prototxt` should be changed.
  for this case, `feed_type` should be 3(which means the data type is string),`shape` should be 1.
  