title: Angular 2 - *ngIf with an else block gives me "Can't bind to 'ngIfElse'", but *ngIf without else block works
body: <p>The example directly from angular.io will not work for me:</p>
  
  <pre><code>&lt;button (click)="show = !show"&gt;{{show ? 'hide' : 'show'}}&lt;/button&gt;
  show = {{show}}
  &lt;br&gt;
  &lt;div *ngIf="show; else elseBlock"&gt;Text to show&lt;/div&gt;
  &lt;template #elseBlock&gt;Alternate text while primary text is hidden&lt;/template&gt;
  </code></pre>
  
  <p>Instead, the browser console errors: "Can't bind to 'ngIfElse' since it isn't a known property of 'div'."</p>
  
  <p>My module looks like this (I am including CommonModule):</p>
  
  <pre><code>import { CommonModule } from '@angular/common';
  import { NgModule }      from '@angular/core';
  import { FormsModule } from '@angular/forms';
  import { BrowserModule } from '@angular/platform-browser';
  
  import { AppComponent }  from './app.component';
  
  @NgModule({
    imports: [
      BrowserModule,
      FormsModule,
      CommonModule
    ],
    declarations: [ AppComponent ],
    bootstrap:    [ AppComponent ]
  })
  export class AppModule { }
  </code></pre>
  
  <p>So I'm not sure what the issue is?  If I simply remove the "; else elseBlock" from the div, the *ngIf statement works as intended.  Therefore, I believe my imports are correct. Any help is greatly appreciated.</p>