feat(Windows): Adds Windows support to react-native-video

This PR adds react-native-windows support to react-native-video.  The Video component is implemented with a XAML MediaPlayerElement.  Most of the features implemented by Android (and some additional ones) are implemented by Windows.

Known issues and missing features include:
* onReadyForDisplay event
* local URI convention (e.g., "broadchurch" in examples changed to require("./broadchurch.mp4")
* `playableDuration` in `onVideoProgress` event is always 0.0
* `playInBackground` is not yet supported
* Volume settings are applied, but the UWP control does not handle it properly

README.md

@@ -80,6 +80,59 @@ Under `.addPackage(new MainReactPackage())`:
 .addPackage(new ReactVideoPackage())
 ```
 
+#### Windows
+
+Make the following additions to the given files manually:
+
+**windows/myapp.sln**
+
+Add the `ReactNativeVideo` project to your solution.
+1. Open the solution in Visual Studio 2015
+2. Right-click Solution icon in Solution Explorer > Add > Existing Project...
+3. Select `node_modules\react-native-video\windows\ReactNativeVideo\ReactNativeVideo.csproj`
+
+**windows/myapp/myapp.csproj**
+
+Add a reference to `ReactNativeVideo` to your main application project.
+
+Using Visual Studio 2015:
+1. Right-click main application project > Add > Reference...
+2. Check `ReactNativeVideo` from Solution Projects.
+
+Manually from `windows/myapp/myapp.csproj`, add:
+```xml
+    <ProjectReference Include="..\..\node_modules\react-native-video\windows\ReactNativeVideo\ReactNativeVideo.csproj">
+      <Project>{e8f5f57f-757e-4237-ad23-f7a8755427cd}</Project>
+      <Name>ReactNativeVideo</Name>
+    </ProjectReference>
+```
+
+**MainPage.cs**
+
+Add the `ReactVideoPackage` class to your list of exported packages.
+```cs
+using ReactNative;
+using ReactNative.Modules.Core;
+using ReactNative.Shell;
+using ReactNativeVideo; // <-- Add this
+using System.Collections.Generic;
+...
+
+        public override List<IReactPackage> Packages
+        {
+            get
+            {
+                return new List<IReactPackage>
+                {
+                    new MainReactPackage(),
+                    new ReactVideoPackage(), // <-- Add this
+                };
+            }
+        }
+
+...
+```
+
 ## Usage
 
 ```javascript