* wayland: upgrade wayland-window
This new version of wayland window considerably simplifies the
window handling for winit, meaning much of the previous juggling
is no longer needed, and the windows will appear even if nothing is
drawn.
* wayland: cleanup unused stuff
X11 and Wayland implementations are now half implemented, however both
still do not correctly break from the inner blocking event dispatch
functions when `wakeup` is called, which they should do.
This expands input events to represent sub-pixel mouse positions, devices responsible for generating events, and raw
device-oriented events. The X11 back end is refactored to make full use of the new expressiveness. Other backends have
had new functionality minimally stubbed out, save for the macos backend which already supports sub-pixel mouse
positions.
