Basic wayland support though wl_shm (#8)

* x11: need to return somethin from processEvents()

* Added wayland support

* Documented how to use wayland support

* wayland: re-attach the buffer to actually trigger an update

* wayland: use the seat_listener

src/x11/X11MiniFB.c

@@ -104,7 +104,7 @@ static int processEvents()
 	KeySym sym;
 
 	if (!XPending(s_display))
-		return;
+		return 0;
 
 	XNextEvent(s_display, &event);