title: enable production mode in angular 2
body: <p>I have been creating web application using Angular 2 and Firebase,
  I want to enable production mode.</p>
  
  <p>main.ts</p>
  
  <pre><code>if (environment.production) {
    enableProdMode();
  }
  </code></pre>
  
  <p>environment.ts</p>
  
  <pre><code>export const environment = {
    production: true
  };
  </code></pre>
  
  <p>environment.prod.ts</p>
  
  <pre><code>export const environment = {
    production: true
  };
  </code></pre>
  
  <p>Then I'm tried ng build -prod; ng serve ,but still not working.</p>
  
  <p>Thanks in advance.</p>