Because idle detection on xwayland is not possible, just assume
that the user is not idle. This also somehow fixes notifications
not disapearing when clicking on them.
When the user doesn't have a seat, or their compositor doesn't support the idle
protocol, we'll assume that they are not idle.
Also, rename wl_output to something that doesn't exist yet.
This commit adds an output struct which abstracts the X11 specific
functions and makes it possible to easily create a drop-in wayland
output.
It also fixes a bug in wayland where notifications won't disappear.
This is because wayland doesn't give access to user input when a
client is not in focus. This way it seems like the user is always
idle. The idle functionality is now disabled in Wayland until proper
support is added.
