Pygame-menu

- Add image example, 377.
- Fix docs.

- Fix ``gain`` and ``pos`` events, 375.

- 🌿.
- Added background color to ``Selection`` class.
- Added ``set_absolute_position``, ``get_last_update_mode``, and ``get_widgets`` to menu.
- Added widget shadow.
- Fixed mouseover/leave for widgets.
- Improve ``WidgetManager``. Now each widget class has its own ``Manager``.
- Improved tests for ``MacOS``.
- New example ``other.maze``.
- New font ``FiraCode``.

- Added support for minified hex colors such as ``f0f`` or ``fff``.
- Added ``float`` and ``float_origin_position`` to ``WidgetManager`` class.
- New example to show widget positioning, 371.
- Simplified file headers.

- Added ``Menu.resize`` method, 369.
- Improve docs.

- Converted all str.format() instances to f-strings, 363, 364, 365.
- Fixed frame and table widget assertion message errors.
- Fixed padding parse issue.
- Improved menu tests.