Add 8 pixels of padding above and left of towerbuffer[_lerp]

In order to fix the weird title screen pixels at the top on deltaframes,
we'll need to have a bit more space at the top. Also to the left, in
case we need a background to scroll from the left in the future.

desktop_version/src/Graphics.h

@@ -238,6 +238,7 @@ public:
 	SDL_Rect bg_rect;
 	SDL_Rect line_rect;
 	SDL_Rect tele_rect;
+	SDL_Rect towerbuffer_rect;
 
 	SDL_Rect foot_rect;
 	SDL_Rect prect;