[ImgBot] Optimize images

*Total -- 129.24kb -> 110.65kb (14.38%)

/Sudoku-Solver-And-Vizualizer/fill.gif -- 1.04kb -> 0.24kb (77.13%)
/ToDo-GUI/image/todo.jpg -- 25.51kb -> 19.36kb (24.13%)
/SNIFFER/sniffer.png -- 84.27kb -> 72.65kb (13.79%)
/Sudoku-Solver-And-Vizualizer/grid.gif -- 18.41kb -> 18.41kb (0.04%)

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Author: ImgBotApp