v1.19.0: Make mouse both scroll and mark in some terminals

Some terminals will convert mouse wheel events to arrow key events, and
on those we don't really need our mouse support (which implicitly
disables the ability to mark text with the mouse).

With this release, for terminals which are known to do this we
automatically disable our built-in mouse support.

See also: https://github.com/walles/moar/issues/53