Add setup gui

Start / Welcome menu (opens a Book GUI) [/gungame setup help]
GUI (Maps or Shops) (http://prntscr.com/nlh7ql) [/gungame setup all]
GUI Maps (http://prntscr.com/nlh6gc) [/gungame setup maps]
GUI Shops (http://prntscr.com/nlh7w2) [/gungame setup shops]

GUI API with pages: https://github.com/MinusKube/SmartInvs
All in commands