In MainActivity.java, protected List<ReactPackage> getPackages() has a different syntaxt compared to the readme

Hi,

Regarding the Android configuration.

The readme suggests:

For react-native 0.29.0 and higher ( in MainApplication.java )

```java
import com.rnfs.RNFSPackage; // <------- add package

public class MainApplication extends Application implements ReactApplication {
// ...
@Override
protected List getPackages() {
return Arrays.asList(
new MainReactPackage(), // <---- add comma
new RNFSPackage() // <---------- add package
);
}
```

In React Native 0.63.4 (ejected from Expo) I get:

```java
@Override
protected List getPackages() {
List packages = new PackageList(this).getPackages();
packages.add(new ModuleRegistryAdapter(mModuleRegistryProvider));
return packages;
}
```

In: `appdir\android\app\src\main\java\com\orgname\appname`

So my bet is to add :
```java
@Override
protected List getPackages() {
List packages = new PackageList(this).getPackages();
packages.add(new ModuleRegistryAdapter(mModuleRegistryProvider));
packages.add(new RNFSPackage()); // <---------- add package
return packages;
}
```

Better ask before. Also, the readme may need to be updated.

Thanks