MAC: Homebrew(代替yum）安装

安装
    ruby -e "$(curl -fsSL https://raw.github.com/Homebrew/homebrew/go/install)"

    最新方式请参见官网首页: http://brew.sh/index.html
    依赖环境 : https://github.com/Homebrew/homebrew/wiki/Installation

使用
    安装:brew install xxx
    删除:brew remove xxx
    查看:brew list
    更新:brew upgrade

    更新brew: brew update