[ImgBot] Optimize images

*Total -- 542.84kb -> 484.11kb (10.82%)

/assets/myAvatar (1).png -- 66.43kb -> 50.56kb (23.89%)
/assets/medium-logo.png -- 68.10kb -> 52.06kb (23.55%)
/assets/myAvatar.png -- 27.28kb -> 22.57kb (17.26%)
/assets/10559931_488539101289461_5878030565438091645_n.jpg -- 381.04kb -> 358.92kb (5.8%)

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Author: ImgBotApp