[ImgBot] Optimize images - #1

*Total -- 38,035.12kb -> 21,152.17kb (44.39%)

/1-hello-world/art/process-quiz.png -- 10,659.29kb -> 80.80kb (99.24%)
/2-variables/piggy-bank/piggybank.gif -- 649.11kb -> 89.16kb (86.26%)
/2-variables/piggy-bank/piggy-bank2.gif -- 3,028.91kb -> 535.94kb (82.31%)
/2-variables/art/declare-intialize.png -- 378.04kb -> 68.57kb (81.86%)
/5-vectors/art/size.png -- 426.45kb -> 93.55kb (78.06%)
/1-hello-world/art/compiler.png -- 281.51kb -> 109.80kb (61%)
/4-loops/art/link-time-error-hint.png -- 52.30kb -> 21.89kb (58.14%)
/4-loops/art/run-time-error.png -- 29.28kb -> 12.62kb (56.9%)
/4-loops/art/link-time-error.png -- 56.04kb -> 25.66kb (54.21%)
/other/Screen Shot 2019-02-01 at 1.28.36 PM.png -- 19.24kb -> 9.30kb (51.66%)
/other/Screen Shot 2019-02-01 at 1.28.26 PM.png -- 17.55kb -> 8.74kb (50.23%)
/community-challenge/prizes.png -- 239.42kb -> 144.14kb (39.8%)
/1-hello-world/art/folder-icon.png -- 28.09kb -> 17.74kb (36.86%)
/blogs/stackoverflow2.png -- 103.78kb -> 66.10kb (36.3%)
/blogs/stackoverflow3.png -- 88.35kb -> 56.40kb (36.17%)
/blogs/stackoverflow5.png -- 92.72kb -> 59.19kb (36.16%)
/1-hello-world/art/folder-icon.svg -- 0.49kb -> 0.31kb (35.86%)
/4-loops/art/circle.png -- 294.61kb -> 190.18kb (35.45%)
/blogs/stackoverflow1.png -- 121.96kb -> 82.15kb (32.65%)
/blogs/stackoverflow4.png -- 122.63kb -> 83.97kb (31.52%)
/1-hello-world/art/program-structure.png -- 177.63kb -> 127.90kb (28%)
/1-hello-world/art/file-name.png -- 18.24kb -> 13.38kb (26.62%)
/2-variables/quadratic-formula/quadratic-formula.png -- 1,177.75kb -> 865.08kb (26.55%)
/3-conditionals-and-logic/logical-operators.gif -- 1,973.60kb -> 1,467.31kb (25.65%)
/4-loops/art/troublemaker.png -- 15.18kb -> 11.90kb (21.65%)
/1-hello-world/block-letters/block-letters.png -- 262.55kb -> 207.36kb (21.02%)
/1-hello-world/block-letters/block-letters-hint.png -- 692.19kb -> 550.56kb (20.46%)
/4-loops/art/compile-time-error.png -- 51.71kb -> 41.45kb (19.85%)
/4-loops/art/compile-time-error-hint.png -- 49.68kb -> 40.68kb (18.11%)
/1-hello-world/art/files2.png -- 17.16kb -> 14.06kb (18.07%)
/blogs/bjarne_stroustrup.jpeg -- 406.16kb -> 346.18kb (14.77%)
/blogs/simon_brand.png -- 103.29kb -> 88.78kb (14.05%)
/1-hello-world/art/files1.png -- 15.02kb -> 13.33kb (11.29%)
/1-hello-world/art/bjarne.gif -- 769.13kb -> 700.10kb (8.97%)
/2-variables/art/data-types.gif -- 680.24kb -> 621.83kb (8.59%)
/community-challenge/highfive.gif -- 3,742.93kb -> 3,437.40kb (8.16%)
/1-hello-world/art/bjarne2.gif -- 773.39kb -> 713.55kb (7.74%)
/1-hello-world/art/terminal.png -- 102.43kb -> 94.70kb (7.55%)
/5-vectors/art/11235.gif -- 483.61kb -> 452.94kb (6.34%)
/community-challenge/gif.gif -- 1,088.50kb -> 1,023.35kb (5.99%)
/1-hello-world/art/process.gif -- 1,356.74kb -> 1,293.78kb (4.64%)
/2-variables/quadratic-formula/graph.gif -- 820.66kb -> 787.72kb (4.01%)
/1-hello-world/art/process.svg -- 19.28kb -> 18.77kb (2.68%)
/3-conditionals-and-logic/harry-potter-sorting-hat/harrypotter.gif -- 1,086.19kb -> 1,062.73kb (2.16%)
/3-conditionals-and-logic/rock-paper-scissors-lizard-spock/RPSLS.gif -- 714.48kb -> 701.17kb (1.86%)
/2-variables/dog-years/dog.gif -- 442.92kb -> 434.90kb (1.81%)
/4-loops/fizzbuzz/fizzbuzz.gif -- 258.71kb -> 254.14kb (1.77%)
/2-variables/piggy-bank/piggy-bank.gif -- 678.74kb -> 667.47kb (1.66%)
/3-conditionals-and-logic/magic-8-ball/magic8ball.gif -- 719.12kb -> 708.70kb (1.45%)
/3-conditionals-and-logic/coinflip.gif -- 408.42kb -> 402.55kb (1.44%)
/3-conditionals-and-logic/coinflip1.gif -- 439.64kb -> 433.46kb (1.41%)
/logo.png -- 14.74kb -> 14.64kb (0.66%)
/3-conditionals-and-logic/harry-potter-sorting-hat/points.gif -- 748.81kb -> 747.82kb (0.13%)
/8-references-and-pointers/memory.gif -- 1,036.51kb -> 1,036.29kb (0.02%)

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