message: docs: add setup scripts to installation document
diff: You are advised to read init.conf file, and modify it as you wish. (this file will configure the basic options of gStore system)
  -gStore is a green software, and you just need to compile it with one command. Please run
  +gStore is a green software, and you just need to compile it with two commands. Please run
  -`make`
  +```
  +sudo ./scripts/setup/setup_$(ARCH).sh
  +make
  -in the gStore root directory to compile the gStore code, link the ANTLR lib, and build executable "gbuild", "gquery", "ghttp", "gserver", "gclient", "gconsole". What is more, the api of gStore is also built now.
  +```
  +in the gStore home directory to compile the gStore code, link the ANTLR lib, 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.
  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.
  