* Update HUB banner image

Passed through tinypng for filesize reduction
Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>

* Update README_cn.md
Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>

* Update README_cn.md
Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>
Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>