title: Error: Cannot find module cross-env using nodemon
body: <p>I have installed nodemon in my app , when I run </p>
  
  <p><code>npm run prod</code> </p>
  
  <p>I  get the following error</p>
  
  <pre><code>module.js:550
      throw err;
      ^
  
  Error: Cannot find module 'C:\Users\jelly\lavalite-new\cross-env'
      at Function.Module._resolveFilename (module.js:548:15)
      at Function.Module._load (module.js:475:25)
      at Function.Module.runMain (module.js:694:10)
      at startup (bootstrap_node.js:204:16)
      at bootstrap_node.js:625:3
  [nodemon] app crashed - waiting for file changes before starting...
  Terminate batch job (Y/N)?
  </code></pre>
  
  <p>Here is package json</p>
  
  <pre><code>{
      "private": true,
      "scripts": {
          "dev": "npm run development",
          "development": "cross-env NODE_ENV=development node_modules/webpack/bin/webpack.js --progress --hide-modules --config=node_modules/laravel-mix/setup/webpack.config.js",
          "watch": "npm run development -- --watch",
          "watch-poll": "npm run watch -- --watch-poll",
          "hot": "cross-env NODE_ENV=development node_modules/webpack-dev-server/bin/webpack-dev-server.js --inline --hot --config=node_modules/laravel-mix/setup/webpack.config.js",
          "prod": "npm run production",
          "production": "nodemon cross-env NODE_ENV=production node_modules/webpack/bin/webpack.js --no-progress --hide-modules --config=node_modules/laravel-mix/setup/webpack.config.js"
      },
      "devDependencies": {
          "axios": "^0.18",
          "bootstrap": "^4.1.3",
          "cross-env": "^5.2.0",
          "jquery": "^3.2",
          "laravel-mix": "^2.0",
          "lodash": "^4.17.4",
          "popper.js": "^1.12",
          "pug": "^2.0.3",
          "pug-loader": "^2.4.0",
          "vue": "^2.5.7"
      },
      "dependencies": {
          "laravel-echo": "^1.4.0",
          "nodemon": "^1.18.4",
          "pusher-js": "^4.2.2",
          "urijs": "^1.19.1",
          "vue-content-loader": "^0.2.1",
          "vue-content-loading": "^1.5.3",
          "vue-filter": "^0.2.5",
          "vue-paginate": "^3.6.0",
          "vue2-autocomplete-js": "^0.2.2",
          "vuejs-auto-complete": "^0.7.0",
          "vuex": "^3.0.1",
          "vuex-i18n": "^1.10.5"
      }
  }
  </code></pre>
  
  <p>what am I doing wrong ? </p>