Nothing happens if the permissions are already granted

When the permissions are already granted, and I try to re-request them, nothing happens. That is because of `PermissionActivity.java`:

```
if (!permissionsToRequest.isEmpty()) {
ActivityCompat.requestPermissions(this, permissionsToRequest.toArray(new String[permissionsToRequest.size()]),
PERMISSION_REQUEST_CODE);
}
```

I think that there should be some `else` statement where some success callback is called.

Now to check if permissions are already granted, I have to call

`PermissionUtils.isGranted(this, permission)` for each permission that I need to check.