message: docs: add make pre to install
diff: @@ -4,13 +4,19 @@ gStore is a green software, and you just need to compile it with two commands. P
  ```
  sudo ./scripts/setup/setup_$(ARCH).sh
  +make pre
  make
  ```
  -in the gStore home directory to compile the gStore code, link the ANTLR lib, and build executable "gbuild", "gquery", "ghttp", "gserver", "gclient", "gconsole".
  +in the gStore home directory to prepare the dependency, link the ANTLR lib, compile the gStore code, and build executable "gbuild", "gquery", "ghttp", "gserver", "gclient", "gconsole".
  (Please substitute the $(ARCH) with your system version, like setup_archlinux.sh, setup_centos.sh and setup_ubuntu.sh)
  What is more, the api of gStore is also built now.
  +Setup scripts and dependency preparation only need to be done once, later you can directly use `make` to compile the code.
  +(For faster compiling speed, use `make -j4` instead, using how many threads is up to your machine)
  +To check the correctness of the program, please type `make test` command.
  +Only if you use the `make dist` command, then you need to run `make pre` command again.
  +
  If you want to use API examples of gStore, please run `make APIexample` to compile example codes for both C++ API and Java API. For details of API, please visit [API](API.md) chapter.
  Use `make clean` command to clean all objects, executables, and use `make dist` command to clean all objects, executables, libs, datasets, databases, debug logs, temp/text files in the gStore root directory.
  