title: Angular2 how to set templateUrl base path
body: <p>In Angular2, I have something like <code>templateUrl = 'templates/app.component.html'</code> during development. But in deployment, i need the url to be something like <code>templateUrl = '/static/angular_templates/app.component.html'</code>. It bites to have to change the url at every single place. Is there an easy way to set a base url and do something like </p>
  
  <pre><code>templateUrl = BASE_TEMPLATE_PATH+ '/app.component.html'
  </code></pre>
  
  <p>so i only need to update <code>BASE_TEMPLATE_PATH</code> when switching from development to production? Thanks!</p>