title: Can't build Angular 4 example with Webpack
body: <p>I recently installed Angular 4 (RC2) and copied the files from the simple <a href="https://angular.io/docs/ts/latest/quickstart.html" rel="noreferrer">Quickstart example</a>. But when I try to build the project with Webpack, I get errors stating that Rxjs can't be resolved:</p>
  
  <pre><code>WARNING in ~/@angular/core/@angular/core.es5.js
  6857:19-40 Critical dependency: the request of a dependency is an expression
  
  WARNING in ~/@angular/core/@angular/core.es5.js
  6883:19-106 Critical dependency: the request of a dependency is an expression
  
  ERROR in ~/@angular/core/@angular/core.es5.js
  Module not found: Error: Can't resolve 'rxjs/Subject' in 'node_modules/@angular/core/@angular'
   @ ~/@angular/core/@angular/core.es5.js 26:0-39
   @ ./app/app.module.ts
   @ ./main.ts
  
  ERROR in ~/@angular/core/@angular/core.es5.js
  Module not found: Error: Can't resolve 'rxjs/observable/merge' in 'node_modules/@angular/core/@angular'
   @ ~/@angular/core/@angular/core.es5.js 23:0-46
   @ ./app/app.module.ts
   @ ./main.ts
  
  ERROR in ~/@angular/core/@angular/core.es5.js
  Module not found: Error: Can't resolve 'rxjs/operator/share' in 'node_modules/@angular/core/@angular'
   @ ~/@angular/core/@angular/core.es5.js 24:0-44
   @ ./app/app.module.ts
   @ ./main.ts
  
  ERROR in ~/@angular/core/@angular/core.es5.js
  Module not found: Error: Can't resolve 'rxjs/symbol/observable' in 'node_modules/@angular/core/@angular'
   @ ~/@angular/core/@angular/core.es5.js 25:0-54
   @ ./app/app.module.ts
   @ ./main.ts
  
  ERROR in ~/@angular/core/@angular/core.es5.js
  Module not found: Error: Can't resolve 'rxjs/Observable' in 'node_modules/@angular/core/@angular'
   @ ~/@angular/core/@angular/core.es5.js 22:0-45
   @ ./app/app.module.ts
   @ ./main.ts
  </code></pre>
  
  <p>I've installed Rxjs 5.0.1, which I think is the version that Angular is expecting. I can't think of anything else to do.</p>