message: update comments in cube example
diff: @@ -340,7 +340,7 @@ impl event::EventHandler<ggez::GameError> for MainState {
  canvas.draw_text(
  &[graphics::Text::new()
  .font("LiberationMono")
  - .text("You can mix ggez and gfx drawing;")],
  + .text("You can mix ggez and wgpu drawing;")],
  dest_point1,
  0.0,
  graphics::TextLayout::tl_single_line(),
  @@ -349,7 +349,7 @@ impl event::EventHandler<ggez::GameError> for MainState {
  canvas.draw_text(
  &[graphics::Text::new()
  .font("LiberationMono")
  - .text("it basically draws gfx stuff first, then ggez")],
  + .text("it basically draws wgpu stuff first, then ggez")],
  dest_point2,
  0.0,
  graphics::TextLayout::tl_single_line(),
  