Previously it was possible to manipulate deleted screens and that
made debugging harder down the line. By catching this early, it
wont be as nightmarish.
It also add some properties such as `border_width`, `border_color`
and `preferred_alignments`.
It also fix a documentation bug where the `margin_topleft` was called
`margins_topleft`. To conform to the documentation, both are now valid
but one should be removed the next time the API changes.
Fixes#1978
Emmanuel Lepage Vallee