Separate YogaLayout library from sample app

Summary: The sample app has library-like elements (i.e. the `YogaLayout` and associated files).  This separates them out into a separate tree.

Reviewed By: emilsjolander

Differential Revision: D4558263

fbshipit-source-id: 33f8cec99661ef20e0e882663b554c12ae33c12f

android/AndroidManifest.xml

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!--
+  Copyright (c) 2014-present, Facebook, Inc.
+  All rights reserved.
+
+  This source code is licensed under the BSD-style license found in the
+  LICENSE file in the root directory of this source tree. An additional grant
+  of patent rights can be found in the PATENTS file in the same directory.
+-->
+
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+          package="com.facebook.yoga.android"
+          android:versionCode="1"
+          android:versionName="1.0"
+          >
+
+  <uses-sdk
+    android:minSdkVersion="15"
+    android:targetSdkVersion="19"
+    />
+
+  <application/>
+
+</manifest>