Provide sample code for most common custom receiver functionality

Hello, Exoplayer cast is awesome playing normal hls and video files. However, there is no documentation for playing hls aes 128 cbc key containing m3u8 in chromecast. If you have made a cast extension, why dont you give a tutorial or project for custom receiver for cast? I could not find anywhere anycode to play hls aes m3u8. Any users who has implemented this kindly share your code. Or the google exoplayer team kindly give a proper code for exoplayer to play hls aes and drm content. So far I have Implemented upto this to play normal m3u8 with custom receiver:
```

const context = cast.framework.CastReceiverContext.getInstance();
const playerManager = context.getPlayerManager();
const playbackConfig = new cast.framework.PlaybackConfig();
playbackConfig.autoResumeDuration = 5;


context.start({

playbackConfig: playbackConfig

});

```