Saving and retrieving music from Android system.

I am currently developing for Android and have gone through a few issues here and it seems there is no way to access the directory where songs are stored? I would like to be able to save mp3's and access them either through my app or with the native Music app. I've tried to implement commit #155 and access `Environment.DIRECTORY_MUSIC` however that seems the constant I get is undefined. I've read issue #323 where they suggest using [react-native-get-music-files](https://github.com/cinder92/react-native-get-music-files) and glancing at the source it seems they are accessing the music files through `android.provider.MediaStore` Is this the correct way to do it? I would like to use react native fs for this task.