Chapter 52: Modifier KeyCode Input Problem in Linux

Regarding Chapter 52: User Interface, the Shift+Number hotkeys are not working, in Linux (Lubuntu 20.04). In my case the keyboard layout is US. It's working exactly as expected on my Windows 10 machine. It seems the modifier key is not being recognized in Linux.

I think this is a different/separate Issue from https://github.com/amethyst/rustrogueliketutorial/issues/8. Repeating the glutin window example used by @mgedmin in https://github.com/amethyst/rustrogueliketutorial/issues/8 yields the following on my Linux machine:
```
DeviceEvent { device_id: DeviceId(X(DeviceId(12))), event: Key(KeyboardInput { scancode: 42, state: Pressed, virtual_keycode: Some(LShift), modifiers: (empty) }) }

DeviceEvent { device_id: DeviceId(X(DeviceId(12))), event: Key(KeyboardInput { scancode: 2, state: Pressed, virtual_keycode: Some(Key1), modifiers: SHIFT }) }
```

In my case the virtual keycodes are Some rather than None, but I am unsure of how to get this to work correctly in Linux.

As a workaround, I tried implementing the suggestion in issue https://github.com/amethyst/bracket-lib/issues/180, but the results of which were unsatisfactory, likely due to my implementation and poor understanding of the library. I'm not quite sure where the "game loop" section of the code should go with regards to the tutorial (I had tried putting it in the tick() function, as shown in their own source code).