Add the ability to provide a native directx texture handle as an image source.

WPF provides D3DImage for interoperability with native code / DirectX.
But D3Dimage are meant for dynamic content rendering and according to its documentation, should be used sparingly.

In my case, I need to load textures for processing in native code, but also display them to the user via a WPF based UI.
The current Implementation forces me to load the texture twice: once via native code and once via WPF ImageSource API.
This is very inefficient, especially for application that loads large amounts of images.

An API such as TextureImageSource that accepts a native handle to a DXGI shared handle is needed to avoid this.