Comment 7 for bug 1781971

In discussion with Andres, this would only impact the 'core' flavor of NGINX. It would not be scoped to include any other packages other than the Main-included ones.

The original request came up because we don't have any way to not fail currently during installation or upgrading if something else is bound to port 80. Rather than changing the fundamentals of the packaging radically such as proposed, it may be easier to simply institute checking if port 80 is bound to or not. (see Bug #1782226 where this is proposed by myself)