add ZBNF app to showcase

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Closes https://github.com/facebook/react-native/pull/6680

Differential Revision: D3102712

fb-gh-sync-id: 2872886bc34128dae3326c664d446ffc8c97df03
fbshipit-source-id: 2872886bc34128dae3326c664d446ffc8c97df03

website/src/react-native/showcase.js

@@ -686,6 +686,12 @@ var apps = [
     link: 'https://itunes.apple.com/us/app/yazboz-batak-esli-batak-okey/id1048620855?ls=1&mt=8',
     author: 'Melih Mucuk',
   },
+  {
+    name: 'ZBNF - Zero Budget Natural Farming',
+    icon: 'https://lh3.googleusercontent.com/gnEBtkUTy89wgbRlEmbETJN9qzHgAAkcvCknWhZbomDRexFAjkU8W-DQFtFygTGeLtA=w300-rw',
+    link: 'https://play.google.com/store/apps/details?id=com.zbnf',
+    author: 'Chandra Sekhar Kode',
+  },
   {
     name: '天才段子手',
     icon: 'http://pp.myapp.com/ma_icon/0/icon_12236104_1451810987/96',