[ImgBot] optimizes images

[ImgBotApp]

Hi! I'm ImgBot. Nice to meet you.

I noticed there were a bunch of images living in your project that weren't totally optimized so I thought I'd make you a PR ;) I use a lossless compression algorithm from ImageMagick so all the images are the same quality and dimensions as before only they take up less space now.

Image processing is tough work, I know, but I never get tired and I never rest - not until all the images on GitHub are totally optimized.

*Total -- 989.43kb -> 562.65kb (43.13%)

/assets/mocha-banner-192.png -- 15.30kb -> 6.35kb (58.49%)
/docs/images/emacs.png -- 591.08kb -> 280.32kb (52.58%)
/docs/images/reporter-dot.png -- 13.15kb -> 7.28kb (44.63%)
/docs/images/jetbrains-plugin.png -- 87.05kb -> 50.34kb (42.17%)
/docs/images/wallaby.png -- 47.87kb -> 33.00kb (31.06%)
/assets/mocha-logo-128.png -- 7.27kb -> 5.19kb (28.62%)
/assets/mocha-logo-192.png -- 10.13kb -> 7.25kb (28.45%)
/docs/images/mocha_side_bar.png -- 214.39kb -> 170.27kb (20.58%)
/assets/mocha-logo-64.png -- 3.20kb -> 2.65kb (17.01%)

[jsf-clabot]

All committers have signed the CLA.

[coveralls]

Coverage increased (+0.05%) to 90.014% when pulling 9cd974c on ImgBotApp:imgbot into 33db6b1 on mochajs:master.

[dabutvin]

👍 happy to help

If you want more prs from ImgBot here, or any of your other projects, feel free to install the GitHub app.

https://github.com/apps/ImgBot

[boneskull]

@dabutvin Please don't send unsolicited PRs from bots.

I'm going to revert this, as we've lost color information on the logos.

[dabutvin]

@boneskull sorry for the trouble.

I logged an issue over at Magick.NET

[Munter]

Also, we already have image optimization as part of the build pipeline. It's completely on purpose to keep the original images unoptimized so we don't lose any information. This lets us remove build time optimizations if they cause undesired data loss

[Bamieh]

@Munter with their implementation you revert a commit. Personally I favor having the optimizations in the build step ONLY because we have a build step. this way we have everything in one place.

[boneskull]

we already have image optimization as part of the build pipeline. It's completely on purpose to keep the original images unoptimized so we don't lose any information

This is an extremely common scenario. I don't see how the bot could be effective, sending PRs to random projects.