title: React app runs locally, crashes when on Heroku error code=H10
body: <p>The app runs fine after an 'npm start' in windows, but when I pull from github into Heroku I just get an error.  </p>
  
  <p>package.json:</p>
  
  <pre><code>{
    "name": "tic-tac-toe",
    "version": "0.1.0",
  
    "dependencies": {
      "react": "^15.5.4",
      "react-dom": "^15.5.4"
    },
    "engines": {
        "node": "6.10.3",
        "npm":"3.10.10"
    },
    "devDependencies": {
      "react-scripts": "1.0.7"
    },
    "scripts": {
      "start": "react-scripts start",
      "build": "react-scripts build",
      "test": "react-scripts test --env=jsdom",
      "eject": "react-scripts eject"
    }
  }
  </code></pre>
  
  <p>and the error log:</p>
  
  <pre><code> app[web.1]: npm ERR!     npm bugs tic-tac-toe
   app[web.1]: npm ERR! Or if that isn't available, you can get their info via:
   app[web.1]: npm ERR!     npm owner ls tic-tac-toe
   app[web.1]: npm ERR! There is likely additional logging output above.
   app[web.1]: 
   app[web.1]: npm ERR! Please include the following file with any support request:
   app[web.1]: npm ERR!     /app/npm-debug.log
   heroku[web.1]: Process exited with status 1
   heroku[web.1]: State changed from starting to crashed
   heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=react-tac-to.herokuapp.com request_id=c3cf2461-1989-4734-a7d5-157eb81c9643 fwd="24.29.73.46" dyno= connect= service= status=503 bytes= protocol=https
   heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=react-tac-to.herokuapp.com request_id=05109629-cbb4-4927-9d13-8a3a37fedb93 fwd="24.29.73.46" dyno= connect= service= status=503 bytes= protocol=https
  </code></pre>
  
  <p>The nature of the problem makes me think this is configuration based, and not in the main app.js code.
  the main file is slightly long, so I'll link to it on Github if you want to see it:
  <a href="https://github.com/owenpercoco/React-Tac-Toe" rel="noreferrer">https://github.com/owenpercoco/React-Tac-Toe</a></p>