Width and height could be made public

[FoamyGuy]

We currently have stored width and height in private properties whose names start with underscore:

Adafruit_CircuitPython_ProgressBar/adafruit_progressbar.py

Line 83 in 247b51d

self._width = width

I think width and height should be provided without the leading underscore. It's very useful to know a views size when trying to place other views "after" or "around" it on the screen. I have a specific example of where this comes into play in my display_layout library here where I am trying to use the size of the view to determine where to place the next view in a vertical or horizontal list on the screen.

Some of the other existing displayio view widgets do provide public access to width and height:

adafruit_display_button provides it's width and height with no leading underscore: adafruit_button.py#L106

adafruit_display_text provides width and height via the public property bounding_box: label.py#L303

OnDiskBitmap and the object that results from adafruit_imageload.load() also have public width and height