Correctly handle _NET_WM_WINDOW_TYPE == _NET_WM_WINDOW_TYPE_DOCK (for dzen2 -dock)

src/handlers.c

@@ -377,3 +377,10 @@ int handle_client_message(void *data, xcb_connection_t *conn, xcb_client_message
 
         return 1;
 }
+
+int window_type_handler(void *data, xcb_connection_t *conn, uint8_t state, xcb_window_t window,
+                        xcb_atom_t atom, xcb_get_property_reply_t *property) {
+        /* TODO: Implement this one. To do this, implement a little test program which sleep(1)s
+         before changing this property. */
+        printf("_NET_WM_WINDOW_TYPE changed, this is not yet implemented.\n");
+}