Added OUYA project file.
Added OUYA project template.
Modified installer script to install OUYA files.

No specific OUYA functionality (GamePad support for OuyaController) yet. That's next.
Extending the way WinRt Game Class can be created

Instead of providing just the type of the class extending Xna Game, you
can provide a factory method that you provide the customizated
implementation.
With this change, you will be able to create a Winrt Game as follows:

static void Main()
{
var factory = new
MonoGame.Framework.GameFrameworkViewSourceByDelegate<EngineStuff>(GameFactory);
///you provide a factory method
Windows.ApplicationModel.Core.CoreApplication.Run(factory);
}

///the method that provides the Game implementation
static EngineStuff GameFactory(CoreApplicationView voceview,
IActivatedEventArgs args)
{
InitialEngineDescription desc = InitialEngineDescription.Default();
desc.useMipMapWhenPossible = true;
EngineStuff engine = new EngineStuff(ref desc, LoadScreen);
return engine;
}