winit

This is just the winit window example with very light modifications:

• The #[mobile_entry_point] annotation generates all the boilerplate extern functions for mobile.
• Logging on Android is done using android_logger.

To run this on desktop, just do cargo run like normal! For mobile, use cargo android run and cargo apple run respectively (or use cargo android open and cargo apple open to open in Android Studio and Xcode respectively).