Using win32 to show the splash screen

The advantage is that

- Fast
The sample https://github.com/kkwpsv/SplashImage cost 100ms and the native WPF splash screen cost 300ms. But I do not use benchmark tests. And it slower than UWP.
- Can use any file path
The WPF can only use the resource file. That means we should use the WPF windows with an image to show the splash screen when we use the file path. But we use WPF windows as splash screen and we will find #297 and #298

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Thanks @weltkante the WPF uses win32 method to show the splash screen and my title is not all right. But the [code](https://source.dot.net/#WindowsBase/System/Windows/SplashScreen.cs,129) need many WPF feature. And I suggest that we can use all win32 methods to create a splash screen that means that this code can run in a console project.