Waybox 0.0.2.1

This is a very minor update to 0.0.2 that enables it to do more than just to show a black screen with wlroots versions 0.6.0 through 0.8.1 with the DRM backend. In technical terms, wlroots 0.9 or higher require a function call to succeed in order to create a new output (i.e. put anything on the screen), but in 0.6 though 0.8.1, that function call will fail, meaning the output won't be created. This call succeeded with the Wayland backend, which I'm using for development until Waybox has enough features to be usable as my daily compositor, so I just caught it.

The solution was just conditional compilation, so that this function will only be called when compiled with wlroots 0.9+.