Feature request: save and load player game data (ex: high scores)
I'd like to make a feature request for two methods to easily save and load player data in a way that's cross-platform and works on web. Maybe the API could look like:

``` python
high_score = pyxel.load_data("high-score")
high_score = int(high_score)
pyxel.save_data("high-score", high_score)
```

Ideally the save data would be placed in a safe directory according to the operating system. The Godot engine uses these paths:

![godot save file locations](https://user-images.githubusercontent.com/928367/231027593-58ee5c62-4a8c-4052-bd15-e370acf1473b.png)

[docs](https://docs.godotengine.org/en/stable/tutorials/io/data_paths.html)

and maybe web could just use `localStorage`?

Just a simple key value store would be enough for most purposes.

Pico-8 has `dset(0, "my data")` and `dget(0)` for similar purposes.

Here are some use cases for why I'm requesting this:

- Save player high score for a shooting game
- Persist and load preferences for things like turning off music, sound effects, camera shake, etc.

Would this be a welcome contribution? I'd be happy to help and open a PR if so. Thanks!