title: Angular 2 passing parameters to constructor throws DI exception
body: <p>I'm wanting to setup a string property on a component in my constructor, but when I try something like this</p>
  
  <pre><code>@Component({
      selector: 'wg-app',
      templateUrl: 'templates/html/wg-app.html'
  })
  export class AppComponent {
  
      constructor(private state:string = 'joining'){
  
      }
  }
  </code></pre>
  
  <p>I get a DI Exception</p>
  
  <pre><code>    EXCEPTION: No provider for String! (AppComponent -&gt; String)
  </code></pre>
  
  <p>Clearly, the injector is trying to find a 'string' provider, and can't find any.</p>
  
  <p>What sort of pattern should I be using for this type of thing? Eg. passing initial parameters to a component.</p>
  
  <p>Should it be avoided? Should I be Injecting the initial string?</p>