title: Error after update: Cannot resolve module 'react/lib/ReactMount'
body: <p>So I was trying to put my react-webpack app on Heroku when I started getting the error that ReactMount was not at React/lib/ReactMount. Then I tried a lot of different stuff and ended up trying to create a new project with the same react-webpack generater. And now I get the same mistake even when running on localhost meaning that it must be due to an update somewhere, right?</p>
  
  <p>Does anyone know anything about this?</p>
  
  <p>I have the following dependencies:</p>
  
  <pre><code> "devDependencies": {
  "babel-core": "^6.0.0",
  "babel-eslint": "^6.0.0",
  "babel-loader": "^6.0.0",
  "babel-polyfill": "^6.3.14",
  "babel-preset-es2015": "^6.0.15",
  "babel-preset-react": "^6.0.15",
  "babel-preset-stage-0": "^6.5.0",
  "bower-webpack-plugin": "^0.1.9",
  "chai": "^3.2.0",
  "copyfiles": "^1.0.0",
  "css-loader": "^0.23.0",
  "eslint": "^3.0.0",
  "eslint-loader": "^1.0.0",
  "eslint-plugin-react": "^6.0.0",
  "file-loader": "^0.9.0",
  "glob": "^7.0.0",
  "isparta-instrumenter-loader": "^1.0.0",
  "karma": "^1.0.0",
  "karma-chai": "^0.1.0",
  "karma-coverage": "^1.0.0",
  "karma-mocha": "^1.0.0",
  "karma-mocha-reporter": "^2.0.0",
  "karma-phantomjs-launcher": "^1.0.0",
  "karma-sourcemap-loader": "^0.3.5",
  "karma-webpack": "^1.7.0",
  "minimist": "^1.2.0",
  "mocha": "^3.0.0",
  "null-loader": "^0.1.1",
  "open": "0.0.5",
  "phantomjs-prebuilt": "^2.0.0",
  "react-addons-test-utils": "^15.0.0",
  "react-hot-loader": "^1.2.9",
  "rimraf": "^2.4.3",
  "style-loader": "^0.13.0",
  "url-loader": "^0.5.6",
  "webpack": "^1.12.0",
  "webpack-dev-server": "^1.12.0"
  
  
  "dependencies": {
  "core-js": "^2.0.0",
  "firebase": "^3.5.2",
  "input-moment": "^0.3.0",
  "moment": "^2.15.2",
  "normalize.css": "^4.0.0",
  "react": "^15.0.0",
  "react-bootstrap-datetimepicker": "0.0.22",
  "react-datetimepicker-bootstrap": "^1.1.2",
  "react-dom": "^15.0.0",
  "webpack": "^1.13.3"
  </code></pre>