[ImgBot] Optimize images

*Total -- 44.09kb -> 29.37kb (33.38%)

/ReadmeFiles/topology.png -- 17.62kb -> 7.86kb (55.42%)
/ReadmeFiles/screenshot.png -- 26.48kb -> 21.52kb (18.72%)

Signed-off-by: ImgBotApp <ImgBotHelp@gmail.com>

Author: ImgBotApp