====== CLI (Command Line Interface) ======

  * https://github.com/jlevy/the-art-of-command-line/blob/master/README-ko.md
  * http://www.lihaoyi.com/post/BuildyourownCommandLinewithANSIescapecodes.html
  * http://egloos.zum.com/sunyzero/v/4282610
  * https://github.com/prompt-toolkit/python-prompt-toolkit
  * https://github.com/facebookincubator/python-nubia