Add Emberall to showcase

Summary:
I'm really excited to finally have been able to share with the world the app that I've been building with React Native for the last six months! Emberall is the best way to save and share family videos, and record special moments with your kids as they're growing up. (vjeux ping me if you want a premium account for free :P ) More details are on our company [blog](http://emberall.com/blog).

I've been heads down for a while just getting this out the door, but I'll try to have a blog post out soon with lessons learned in getting the app finished and published in the App Store.
Closes https://github.com/facebook/react-native/pull/7657

Differential Revision: D3328341

Pulled By: vjeux

fbshipit-source-id: ef0c6a8e68fa1cab6caf6daa1a0d7d177d752e7f

website/src/react-native/showcase.js

@@ -1008,6 +1008,12 @@ var apps = [
     link: 'http://android.myapp.com/myapp/detail.htm?apkName=com.tencent.karaoke',
     author: '石玉磊',
   },
+  {
+    name: 'Emberall',
+    icon: 'http://assets.emberall.com/images/app/icons/medium.png',
+    link: 'https://emberall.com/',
+    author: 'Kyle Corbitt',
+  },
 ];
 
 var AppList = React.createClass({