Installed webpack

- Installed webpack and webpack-cli
- Added a start script in package.json which calls webpack
- Made an index.js file, which is the file webpack looks for by default
- Webpack spits out our code in dist/main.js by default
- Currently our main app code has nothing to do with webpack, but it will soon

index.html

@@ -44,4 +44,5 @@
   <script src="./src/app/utils/inputs-are-valid.js"></script>
   <script src="./src/app/utils/parse-inputs.js"></script>
   <script src="./src/app/app.js"></script>
+  <script src="./dist/main.js"></script>
 </html>