Snat

- Improve Settings class:
- Replace properties with TypedValue (seems to improve performance)
- Improve documentation and typing
- Fix GameList.select_game method for All Games selection (was emitting a signal)
- Remove achivement sorting

- Fix double game selection on startup (make things inconsistent and is useless)

- Load dinamically about.py and input_dialog.py on need (better startup time)

- Add documentation
- Fix typing
- Remove useless GameList serialisation with `pickle`

- Add icon
- Add version in logs
- Add menu bar and About dialog

- Add application version
- Fix file logging handler level