Use Cmd instead of Ctrl on macOS

[rom1v]

Use Cmd instead of Ctrl for all shortcuts on macOS.

Fixes #642

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Mac users, please confirm that it works as expected 😉

cc @npes87184 @carstenhag @zhuxianfeng13 @AoDevBlue @numbermaniac

[carstenhag]

Hey, I've compiled and tried it out just now.

Cmd+M does not work as excepted, because Cmd+M is a mac (global?) shortcut to minimize the window.

The other shortcuts work fine. One thing though, which I guess is unrelated: I have no way to middle-click on a Magic Mouse. On the Macbook touchpad it's possible but really difficult depending on the touchpad settings. It would be good to provide an alternative shortcut for that.+

Sadly, Cmd+H stands for hide this window on the Mac, so we can't/shouldn't use it.

[rom1v]

@carstenhag Thank you very much for your tests and feedback.

So I updated this PR to keep Ctrl for Ctrl+h and Ctrl+m.

I have no way to middle-click on a Magic Mouse. On the Macbook touchpad it's possible but really difficult depending on the touchpad settings. It would be good to provide an alternative shortcut for that.

What would you suggest? I will probably use Ctrl+click or Shift+click for "pinch to zoom". Maybe Ctrl+Right-click or something like that?

[carstenhag]

Yeah, Cmd+Click seems good to me.

[rom1v]

Cmd+click for HOME or pinch-to-zoom (not implemented yet)?

[carstenhag]

Not really sure what you mean by pinch-to-zoom :)

Cmd for Home, Shift for that, seems good to me. We can still test it later.

[rom1v]

Not really sure what you mean by pinch-to-zoom :)

#24