Refactor MenuBar and StatusBar to be adornments

[tig]

This is a sub-issue of:

• Finish Adornments (master Issue)  #2994

Todo

• Reimplemen these views based on Bar. See Create a new Bar view to replace StatusBar (and eventually MenuBar) #3073
• Remove the dependency between these classes and Toplevel and enable any view to host a menubar or statusbar (or any View).
• By default Window will have the menubar and statusbar's added to it's Border/Adornment Frame but they will be Visible = false by default. We'll expose helper properties to access them:

win.MenuBar.Visible = true etc...

[tig]

Not entirely sure this is needed.

[BDisp]

Not entirely sure this is needed.

I don't think this make senses because any view has adornments and the question must be should MenuBar and StatusBar be created in the parent adornments? Now it's possible to add it anywhere the user want it, right? If affirmative then this can be closed.

[tig]

I had two reasons for suggesting this:

1. Views can't render outside of their Viewport. That's a new LAW for v2. But the same law does not apply to Adornments because they are system managed. Menu, in particular, has the need to render outside of the Viewport because a dropdown may be larger than the view.

2. The Toplevel code that tries to be "smart" about Menu/Statusbar is clumsy and bug ridden. I was thinking putting them in Padding might enable this to be simplified.

I still think 1) is semi-valid. I don't think 2) is valid anymore.

I'm going to close this for now though as there's not enough justification.