fix(aio): do not force live-example embedded image to 100% size

This made them look too big, generally. Leaving them with no size means
that they will look reasonable in large viewports and switch to 100% width
in narrow viewports.

aio/src/app/embedded/live-example/live-example.component.html

@@ -4,7 +4,7 @@
     <div *ngIf="showEmbedded" title="{{title}}">
       <aio-embedded-plunker [src]="plnkr"></aio-embedded-plunker>
     </div>
-    <img *ngIf="!showEmbedded" (click)="toggleEmbedded()" [src]="plnkrImg" width="100%" height="100%" alt="{{title}}">
+    <img *ngIf="!showEmbedded" (click)="toggleEmbedded()" [src]="plnkrImg" alt="{{title}}">
     <p *ngIf="enableDownload">
       You can also <a [href]="zip" download title="Download example">download this example</a>.
     </p>