+ should be in the navigation bar

[VPhung24]

Is your feature request related to a problem? Please describe.
it's more intuitive in iOS for the + button to be in the navigation bar. Not a button in the lower right hand corner

Describe the solution you'd like
The button should be the left navigation button

[VPhung24]

in #28 but should be a feature request

[cambardell]

Thanks @VPhung24, assigned!

[cambardell]

I think this means we can remove the ZStack from ContentView. I might be wrong but I think it's only purpose was that floating button.

[VPhung24]

makes sense. on it!