Define CFBundleName in macOS bundle

[fwcd]

CFBundleName declares the menu bar name as documented here and lets us display the name "Mixxx" with proper capitalization in the macOS menu bar:

Previously, it looked like this:

[Holzhaus]

Thanks for looking into it. I cannot verify if it works, and according to the docs this should not be necessary because we already set CFBundleDisplayName:

The system may display it to users if CFBundleDisplayName isn't set.

However, if you tested it, I see no reason to not merge this.

[fwcd]

I was a bit confused by the docs too, apparently they are mainly focused on iOS where the concept of a menu bar doesn't exist. In my tests and according to this stackoverflow post, it seems to be used for the menu bar indeed.

Can't hurt to declare it, however it may be, though. :)

[Holzhaus]

Alright, then let's merge it! 👍

[ronso0]

@fwcd I think even though this is a small change we need you sign the Mixxx contributor agreement.
Please comment here when done.

Thank you!

[fwcd]

@ronso0 Done!