title: cross-env: command not found on Windows OS
body: <p>I run <code>npm install</code> on my Mac, and command <code>cross-env NODE_ENV=development node build/dev-server.js</code> successes. Then I copy the whole project to my Windows computer, but the command <code>cross-env NODE_ENV=development node build/dev-server.js</code> failes, telling me <code>cross-env: command not found</code>. Is it due to different OS? Because I can't connect npm registry on my Windows OS. What can I do then?</p>