MAC终端补全命令和参数
参考： https://segmentfault.com/q/1010000000636402
ruby -e "$(curl -fsSL https://raw.github.com/Homebrew/homebrew/go/install)"
brew install bash
brew install bash-completion
echo 'if [ -f $(brew --prefix)/etc/bash_completion ]; then . $(brew --prefix)/etc/bash_completion; fi' >> ~/.bash_profile
sudo sh -c 'echo "/usr/local/bin/bash" >> /etc/shells'
chsh -s /usr/local/bin/bash
