Add some Keys

[rustbasic]

Add some Keys :

CapsLock,
NumLock,
ScrollLock,

Alt,
AltRight,
Control,
ControlRight,
Shift,
ShiftRight,

• Related #2041
• Closes #3636
• Related #3653

[github-actions[bot]]

Preview available at https://egui-pr-preview.github.io/pr/5400-patch150 Note that it might take a couple seconds for the update to show up after the preview_build workflow has completed.

[JRoper18]

Hey, I'd love this feature. My usecase is having special stuff happen when someone hits the CTRL key. Any hope of getting it merged in?

[emilk]

This doesn't work at all in the web demo at https://egui-pr-preview.github.io/pr/5400-patch150/:

[rustbasic]

While it might not work well on the web because the browser takes focus, this isn't the issue with this commit. We'll need an additional commit for the modifiers.