Add menu bar

[cuba]

I think it would be really nice to add a menu bar so that we can close the Whisky window and still have its applications running or access certain useful tools.

I have created this POC for your consideration. Changes include

1. Closing window no longer terminates the application
2. Can perform some common commands right from the menu bar without having the application in focus
3. Uses pure vanilla SwiftUI components

[IsaacMarovitz]

I like the concept! Looks like it could be helpful

[cuba]

I like the concept! Looks like it could be helpful

Glad you like the concept! I can develop it further if you think it's worthwhile. I don't think it should become too bloated because it should just perform some of the most common functionality. But feel free to put any comments or suggestions in code or here where you would like to see this go, the file organization, etc when you can.

So if we're in agreement, I'd like to take this further I'll have to touch some more of your written code just so the menu bar and the application stays in sync because I don't think they do right now.

[IsaacMarovitz]

@cuba Rebase needed after recent reorganisation

[cuba]

@cuba Rebase needed after recent reorganisation

Done, I had to rebase it on my newer settings fixes PR so that the changes in the menu bar / in the app are in sync. Added icons to pinned items as well