* Detect panics during initialization and show them to the user
* PanicHandler now also logs the panics
* Add example of how to call into your app from JS
* Refactor: break out AppRunner and AppRunnerRef to own files
* Hide AppRunner
* Simplify user code
* AppRunnerRef -> WebRunner
* Better docs
* Don't paint until first animation frame
* Update multiple_apps.html
* Update web demo
* Cleanup and fixes
* left-align panic message in html