message: fix doc/compile and python/examples/encryption/get_data.sh by HexToString
diff: wget --no-check-certificate https://paddle-serving.bj.bcebos.com/uci_housing_example/encrypt.tar.gz
  tar -xzf encrypt.tar.gz
  +cp -rvf ../fit_a_line/uci_housing_model .
  +cp -rvf ../fit_a_line/uci_housing_client .
  