Update C# wrapper to support both desktop and UWP projects

Summary:
The C# wrapper project has been changed to a NETStandard (1.1) PCL allowing it
to be consumed by any project targeting .NET4.5 or greater including .NETCore
and UWP projects... The C# wrapper uses P/Invoke to call into the Native Yoga
DLL...

The "Yoga" C++ project has been updated to support ARM builds...

Added the ability to generate nuget packages for the C# wrapper that supports
copying the native DLLs to the target output directory.

Closes: https://github.com/facebook/yoga/pull/283

Reviewed By: splhack, emilsjolander

Differential Revision: D4381455

Pulled By: JoelMarcey

fbshipit-source-id: e6dc4190caa824ac63d5d5ee2eb4c7914efbb00f

csharp/Windows/Facebook.Yoga/Properties/AssemblyInfo.cs

@@ -0,0 +1,29 @@
+/**
+ * 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.
+ */
+
+using System.Reflection;
+using System.Resources;
+using System.Runtime.InteropServices;
+
+[assembly: AssemblyTitle("Facebook.Yoga")]
+[assembly: AssemblyConfiguration("")]
+[assembly: AssemblyCompany("Facebook, Inc.")]
+[assembly: AssemblyProduct("Facebook.Yoga")]
+[assembly: AssemblyDescription("A subset of CSS's flexbox layout algorithm and box model.")]
+[assembly: AssemblyCopyright("Copyright (c) 2014-present, Facebook, Inc.")]
+
+[assembly: ComVisible(false)]
+
+[assembly: Guid("75bb7605-e54b-4ede-8f5a-ff1f24464236")]
+
+[assembly: NeutralResourcesLanguage("en")]
+
+[assembly: AssemblyVersion("1.0.0.0")]
+[assembly: AssemblyFileVersion("1.0.0.0")]
+