title: Endless loop on installing Expo CLI
body: <p>I try to execute command <code>npm start</code> on terminal on my Mac. 
  It prompts me to install Expo CLI , I say Y,  wait until installation to finish, then I end up in an endless loop where it keeps prompting me to install Expo CLI again:</p>
  
  <pre><code>This command requires Expo CLI.
  Do you want to install it globally [Y/n]? y
  Installing the package 'expo-cli'...
  Expo CLI installed. You can run `expo --help` for instructions.
  This command requires Expo CLI.
  Do you want to install it globally [Y/n]? 
  </code></pre>
  
  <p>Any ideas why I'm having this?</p>