assetPath and audio file placement

**Description of the bug:**
In the Readme.md the following is stated:

```
All audio place in specific platform folder
Andoid: android/app/src/assets
iOS: ios/App/App/sounds
```
This seems to be incorrect!

**Suggestion for a fix:**
All audio should be placed inside the specific folders:
Android: android/app/src/main/assets
iOS: ios/App/App/public/assets/

Note: in the case of Android the `assethPath` is just the filename with the extension like `'sound.mp3'` but in the case of iOS
you need to specify more details like: `assetPath: 'public/assets/sound.mp3'`